“Midday in frontof shepherd’s bush market in London, England. An up-and-coming, lively, and diverse area. November 2021"

Spring 2022 San Diego Community College Student Anthropology Journal

Edited by Nicholas Palos

Published by Arnie Schoenberg

Cover Photo by Dania Palafox


Volume 6 Issue 1

Spring, 2022

latest update: 6/16/22

Creative Commons License CC BY-NC

Unless otherwise noted, this work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

More issues at http://arnieschoenberg.com/anth/journal/

contact: prof@arnieschoenberg.com

Table of Contents

Preface by Nicholas Palos

The Importance of Repatriation: Private Museums Compliances with NAGPRA” by Daniayarit Garcia

Race and beauty: How it has Evolved”  by Abigail Fuentes-Cervantes and Michael Stewart

Recognizing and Challenging Racism in Healthcare” by Maria Baez

Evolution’s effects on the flight deck: Orientation and Relative Movement” by Stephen Wortham

Human Health Effects of Genetically Modified Organisms” by Cory Horgan

Evolution of Oral Disease and Pathogens” by Angel Madrigal

History and Summary of Xenotransplantation of Pig Organs to Humans” by Alex Pomeranz

Can Man Pass Down the Intangible?” by Jontel Scott

Bipedalism in Australopithecines” by Sergio Armenta

Habits of a Chimpanzee” by Laura Young

Preface by Nicholas Palos

Students from San Diego Mesa, Miramar, and City College have each submitted an informative article that reflects their specific anthropological interests for the 2022 San Diego Community College Student Anthropology Journal. Each article submitted provides detailed research about anthropology topics that include: racism, the evolution of human health, and the history of mankind and our closely related primate species. The articles will be categorized according to the relevance of each topic. Read and learn about the different perspectives that students in the San Diego Community College District have to offer in this year's catalog.

San Diego Mesa College Student, Daniayarit Garcia, has written the article titled, “The Importance of Repatriation: Private Museums Compliances with NAGPRA”, that is about how private museums in the U.S are now required to release power and ownership of all artifacts and burial remains to the respective Native American tribes, after many private museums sought and received federal aid during the 2019 pandemic. Archaeological findings hold the answers and evidence to modern intelligence and will continue to provide important knowledge as new prehistoric and ancient evidence is brought to the modern world. Readers will learn how private museums were not required to give ownership or a decision-making role to Native tribes during or after excavations on their land.

Future San Diego State University students, Abigail Fuentes-Cervantes and Michael Stewart co-wrote the article titled, “Race and beauty: How it has Evolved”, that is about how race and beauty have evolved throughout history. Abigail and Michael explain interesting concepts and ideas about how humans generally choose their romantic partner based on what race that person is and how beautiful that person is. Readers can expect to learn an interesting perspective on beauty and race that is more scientific than negative.

Third year San Diego City College Student, Maria Baez, has written the article titled, “Recognizing and Challenging Racism in Healthcare”, that sheds light on the racism that is experienced in the field of health care. Racism is a major concept that dates to ancient times in human history. Maria explains how minorities are treated unfairly, and how African Americans are generally singled out from the rest of the minorities in America and are neglected in medical settings. Readers will learn interesting statistics about the racism that occurs in our country's healthcare system.

Stephen Wortham, a second-year college student who aims for a degree in Aviation Science, has written the article titled, “Evolution effects on the flight deck: Orientation and Relative Movement”, that is about how our bodies react negatively to flying. Humans having the ability to fly at their own convenience will be remembered as one of the most significant accomplishments of our species’ existence. Readers will learn how flying over a long period of time can negatively affect overall human health.

Future San Diego State student Cory Horgan, has written the article titled, “Human Health Effects of Genetically Modified Organisms”, about the health effects of genetically modified organisms. GMOs have revolutionized modern agriculture, which has allowed the world’s population to continue to be fed and decrease the risk of food shortage. Readers will learn interesting facts about GMO’s and decide for themselves whether they agree with the practice or not.

Third year San Diego City College Student, Angel Madrigal, wrote the article titled, “Evolution of Oral Disease and Pathogens”, that reviews the important history and evolution of deadly and not so deadly pathogens and diseases. Pathogens and diseases have affected humans for thousands of years and have caused many epidemics including the most recent Covid-19 pandemic. Readers will learn the history of the diseases and pathogens that have taken the lives of many ancient humans and how our methods and technology have improved in some areas since then.

Alex Pomeranz, a student at San Diego City College, has written the article titled, “History and Summary of Xenotransplantation of Pig Organs to humans”, that is about the history of the xenotransplantation of pig and other animal organs to humans, for his entry in the San Diego Community College Student Anthropology journal. Alex explains the importance of xenotransplantation procedures and how society can benefit from them, he also touches on some of the dangers that can arise from the procedure as well. Alex focuses on patients that need extreme medical help and how resorting to the procedures can potentially save lives as technology and human intelligence progresses. Readers can learn about the outcomes of different xenotransplantation procedures that have taken place in history.

Former U.S Navy Sailor and current San Diego Miramar student, Jontel Scott, has written the article titled,“Can Man Pass Down the Intangible?”, that is about how human traits like feelings and behaviors have been passed down through generations. Thinking patterns, feelings and behaviors are very important aspects of humans because the traits give humans a sense of character. Readers can learn the specifics of how certain behaviors and ways of thinking have been passed down through various ways.

San Diego City College student, Sergio Armenta, has written the article titled, “Bipedalism in Australopithecines”, that is about the evidence of bipedalism found in Australopithecines. The discovery of Australopithecines was very important in Anthropology because of how they were believed to walk on two feet, like modern humans. Readers can find out the regions that evidence of Australopithecines were found in and learn exactly what kinds of artifacts and remains were found during the excavation process.

Future Sacramento State University student, Laura Young, has written a field work article titled, “Habits of a Chimpanzee”, that explains her findings during her time spent in the Chimpanzee section of the Sacramento Zoo. Primates, including the chimpanzee are generally believed to be the species of animal that are most similar to humans. Laura records the behaviors of the chimpanzees present in the Sacramento Zoo during her few visits. Readers will learn new and interesting facts about how chimpanzees behave over an extended period of time.

These students have dedicated their time and energy, and have produced valuable research for this year's journal. Each student prepared their articles with hopes of informing the rest of the San Diego college community of their unique perspectives on important Anthropological topics that are relevant and important to the history of the human species.


“The Importance of Repatriation: Private Museums Compliances with NAGPRA” by Daniayarit Garcia


The Native American Graves Protection and Repatriation Act (NAGPRA) was enacted in 1990 by Congress to establish a legal process of repatriation of cultural resources and human remains of Indigenous tribes to their rightful owners. During the Covid-19 pandemic, many museums recurred to financial aid from the federal government. This aid was available to these museums in the form of the American Rescue Plan Act of 2021 or as loans from government agencies such as the Small Business Administration (Indian Country Today 2021). NAGPRA requires museums that accept federal funding to implement the procedures that are established by the act.

In the attempt to raise awareness among local and regional museums, I conducted a literature review to gather information about the impact of NAGPRA since its enactment in 1990. With the information I was able to gather, I created a petition and a sample letter that can be sent to museums that are subject to compliance with NAGPRA due to the acceptance of Federal funding to continue their operations.

I hope that these initiatives are considered by museums to establish the procedures that NAGPRA requires to foment relationships that will be beneficial for the development of genuine cultural change in educational institutions. Consultation with indigenous tribes on exhibiting their cultural possessions is beneficial for the development of the humanistic aspect of scientific approaches as it enriches the value of their history.


In Anthropology, the study of human societies and their biological development requires a partial holistic approach to encompass the broad aspect of what it means to be human (Schoenberg 2022, 1.2.1). We have evolved to acknowledge that humans are unique, cultural species, and interminabile to study in all aspects. We have also acknowledged that our past has an impact in the way we currently live, and this is why we value it.

Humans have developed institutions that exhibit the value that is attached to the past. These institutions are known as museums. However, there are traces of the past of cultural groups that these colonial institutions have appropriated to exhibit in a misrepresentative way. There are public, private, and federal museums in the United States whose collections are composed by cultural resources of Indigenous groups.

The Native American Graves Protection and Repatriation Act (NAGPRA) was enacted in 1990 by Congress as a response to the pressing demand of Native Americans to have control and access to their cultural possessions and human remains of their ancestors. In order to have cultural resources of Indigenous groups to be returned, or to be protected and respected if they are under possession of public, private, or federal institutions, alliances between these groups and institutions must be established.

NAGPRA requires museums and Federal agencies to conduct an inventory of their collections as part of the process of repatriation (Association on American Indian Affairs 1992). During the Covid-19 pandemic, many museums resorted to Federal aid to continue their operations. Due to this, private museums that had no ties to any Federal agency prior to the pandemic had not been legally required to adhere to NAGPRA. Now, it is of utmost importance that museums that are benefiting from Federal funding to operate are being held accountable in the implementation of the process of repatriation.

Action anthropology serves the purpose of using anthropological knowledge to better guide political action (Schoenberg 2022). One of the goals of action anthropology is to provide practical support to the communities within anthropologists work (Rubenstein 2018). Collaboration in these instances to seek for the best outcomes for communities facing an issue is crucial to achieve that outcome. In this case, forging relationships to better represent the cultural resources of indigenous tribes allow for the establishment of restorative justice practices. This is, the implementation of procedures of repatriation as means of remediation.


I conducted an action anthropology project based on methods of a literature review. The process of development of this project consisted in doing archival research about the enactment of NAGPRA in 1990 and its influence throughout the years. With the information provided by the official document of the law and studies, I wrote critical reviews as part of the literature review portion of the project.

Other sources consisted of articles about the subjectivity of museums that received Federal stimulus due to the pandemic. One of the articles reviewed for this project, titled “Private museums could face NAGPRA scrutiny” discusses two specific cases about private collections of museums that are part of a larger institution that has received Federal funding. The second case discussed in the article refers to the “End of the trail” museum, which is part of a roadside attraction in California, known as Trees of Mystery. The private collection consists of several Native Americans artifacts such as masks, carvings, and basketry. During the pandemic, Trees of Mystery received $650,000 in loans from the federal Small Business Administration to continue with their operations (Indian Country Today 2021).

Learning about these cases made me realize that there might be more museums that have benefited from federal aid throughout the pandemic, and are not aware that they are required to comply with NAGPRA. As part of the completion of this action anthropology project, I also reached out to a Native monitor of a monitoring organization based in California.

Finally, an analysis of the information collected was done in order to utilize it to create a sample letter that can be sent to museums which, due to the acceptance of Federal funds, are now subject to compliance with NAGPRA. It is worth to note that the aim of this letter is to also emphasize the importance of repatriation regardless of legal duty; rather, focusing on a sense of moral duty.


This project consists of a campaign that included a petition and a letter. They were written with the intention to spread awareness about NAGPRA and to help the enforcement of the policy, especially at a time in which it can be widely spreaded. The petition covers concepts such as cultural affiliation and decolonization, which are important for museums to acknowledge if they are to establish honest and fruitful relationships with Indigenous tribes as part of their practices (See Appendix A). The letter aims to target those museums that are partly or largely federally funded or are part of a larger institution that has received Federal aid during the pandemic (See appendix B). I hope that these initiatives help in the enforcement of the policy, as well as to raise awareness about NAGPRA and its purpose.


The implementation of NAGPRA should be considered by all museums across the United States regardless of being legally required to do so. Beyond being an act that some museums are subject to comply with, NAGPRA should be rethought as a standard museum organizational practice to intensify the voices of Indigenous communities.

NAGPRA highlights the importance of representation and accurate protection of indigenous peoples artifacts and human remains. It is through these cultural resources that they can be accurately recognized and represented. It is the right of Indigenous tribes to have their cultural property be properly represented and handled.

 Museums that currently possess cultural patrimony of Native American groups as part of their collections, regardless if they are legally obligated to repatriate it by NAGPRA, should consider complying to the regulations stated by the act. The purpose of the implementation of NAGPRA in the future should be done in order to foment the righteous practices that these groups deserve as the result of the injustices that they have, and still continue to suffer due to colonial practices.


Arias, Catherine. (2018). “From Exploration to Equity: A Museum’s Journey Toward Decolonization” https://mdsoar.org/bitstream/handle/11603/13485/JRRP2019_Arias_grad.pdf?sequence=1&isAllowed=y

Kuprecht, K. (2012). The concept of “cultural affiliation” in NAGPRA: its potential and limits in the global protection of indigenous cultural property rights. International Journal of Cultural Property, 19(1), 33-63. https://doc.rero.ch/record/296470/files/S0940739112000057.pdf

NAGPRA compliance. (n.d.). Association on American Indian Affairs. https://www.indian-affairs.org/nagpra-compliance.html

National Congress of American Indians. (n.d.). Cultural protection & NAGPRA. NCAI. https://www.ncai.org/policy-issues/community-and-culture/cultural-protection-and-nagpra

Kelley, N. (2021, May 16). Private museums could face NAGPRA scrutiny. Indian Country Today. https://indiancountrytoday.com/news/private-museums-could-face-nagpra-scrutiny

Rubinstein, Robert. (2018). Action Anthropology. 1-7. 10.1002/9781118924396.wbiea2230.

Schoenberg, Arnie. (2022). Introduction to Physical Anthropology. https://arnieschoenberg.com/anth/bio/intro/index.html

Appendix A: Petition to Federal, Public, and Private Institutions to Comply with NAGPRA

I ask that if you support the goals of NAGPRA to agilize the process of repatriation, truthfully and respectfully exhibit indigenous remains and objects, and establish a bracing relationship between Native American Groups and Federal, public, and private agencies, you take action by agreeing with the following points and adding your signature at the bottom of this document.

  1. Repatriation Process Accountability


Federal agencies that have complied with NAGPRA have contributed to advancements in osteology. This was possible due to the accelerated process of repatriation that was motioned by the implementation of the policy. Having the collections of Native American skeletons from these federal agencies be analyzed before properly returning them to their significant relatives has increased the amount of osteological data gathered that has helped fill statistical gaps. (Rose, Green, and Green 1996)

Action Item:

  1. Provision of inventory and repatriation data. In order to enforce accountability Federal, public, and private institutions should provide annual reports on their inventory to track the number of skeletons and objects studied, in the process of repatriation, and completely repatriated.

  1. Decolonization Process Accountability


The San Diego Museum of Us is currently undergoing a process of decolonization to better represent the past and meaning of Native American remains and objects and to promote equity amongst the local communities. The process included the forging of a relationship between the institution and the Kumeyaay community. The pressing demand of this native group for the remains and objects of their people to be recognized as their cultural property led the institution to recognize its colonial background and enforce NAGPRA regulations. (Arias 2018)

Action Item:

  1. Recognition of ownership and cultural affiliation. I urge for Federal, public, and private institutions to release statements that recognize Native American ownership of remains and objects that make up their collections, as well as start the process of repatriation if demanded by a native group.


(please include your full name, school and department affiliation, and whether you are a faculty member or a student OR the name of the organization endorsing this letter)


Appendix B: Sample Letter

Dear Private Museum,

Due to the federal American Rescue Plan Act of 2021 fund that the institution accepted as to continue its operations during the Covid-19 pandemic, it may be subject to comply with the Native American Graves Protection and Repatriation Act (NAGPRA).

This procedure requires public institutions, federal agencies, and private collections –where applicable, which is the case of your institution– to inspect their inventory of their collection and create a report that specifies the manner of acquisition, location of origin, and establishes the existence of cultural affiliation, if any.

It is not required by the law for the group that files the claim to demand subsequent actions from the institution that is in possession of the cultural items or human remains. Nonetheless, subsequent action is commonly demanded from indigeous groups, and they determine whether to have their possessions given back, or to grant right of possession.

By granting the right of possession, the opportunity to forge a connection between museums and federal agencies arises. Relationships between museums and indigenous peoples are beneficial for the proper representation of indigenous communities and it is also beneficial for scientific advancements. This is partly due to the provision of a time frame for private museums to go through the inventory of their collections, which accelerates the process of the analysis of human remains and collection of data from this process.

Under NAGPRA, private institutions that accept federal funding are subject to compliance with the policy. According to USAspending.gov, your private museum received a loan from the federal government in May of 2020. Due to the acceptance of this loan, you may be subject to comply with the policy. I encourage your private institution to contact your local NAGPRA office to learn more about the steps you should take to comply with the policy.

Thank you for your consideration.


Daniayarit Garcia

About the Author:

Having been a college student for two years now, I am committed to continue an educational journey to acquire an Urban Studies bachelor’s degree. By the end of the spring term, I would have obtained four different associate degrees: one in Business Administration, one in Law, Public Policy and Society, one in Geography, and one in Language Arts & Humanities.

I am influenced by my environment in the work that I do. Born in San Diego, California and raised in Baja California, Mexico, I realize that growing up in a border city has allowed me to be part of a complex, yet rich dual culture. Given this environment that has helped shape my identity, I usually find myself drawn to participate in the planning and structure of projects to improve the dynamics of my community. I am currently serving as a senator in the student government group of San Diego Mesa College (Associated Students), and I am also part of the San Diego Mesa College environmental and sustainability club: TerraMesa.

“Race and beauty: How it has Evolved”  by Abigail Fuentes-Cervantes and Michael Stewart

When one examines the genetic and cultural origins of self or deals with the evolution of humans and the capacity humans have for adaptation to environmental stresses through natural means and sexual means, then Biological Anthropology, a subfield of Anthropology, is being studied. Through this, evolution, race and beauty were created. Most societies categorize people by race, even though anthropologically, humans of different colors are biologically the same and may even share ancestral genes that determine the deepest of blacks to the lighter European skin colors. What humans have viewed as beautiful has evolved alongside the species, and facial structure is a huge component of beauty. Humans, and other animals in nature, are drawn toward beautiful traits–because of this, those traits evolve to become more and more pronounced.

Beauty is something that can be passed down from parent to child from both a biological and cultural standpoint, similarly, agriculture and livestock can be bred for better yields. Through selective breeding of vegetation and animals, farmers are able to produce larger and better produce and livestock (Schoenberg 2022, This type of breeding is used to force the desired trait. The farmers are selecting the traits desired in the future crops/livestock and give those characteristics the best chance to be reprised. By doing this over and over a farmer can change a vegetable over time to create something that is more abundant, “We see in the archaeological record of Mesoamerica how teosinte was selected over thousands of years and became corn” (Schoenberg 2022, Steven W. Gangestad and Glenn J. Scheyd offer an excellent scientific explanation of natural selection in which they state:

The word adaptation has two meanings in evolutionary biology (Gould & Vrba 1982). It is the process by which natural selection modifies the phenotype and generates traits whose effects facilitate the propagation of certain genes over others, thereby causing evolution. It also refers to the end products of that process—i.e., the traits that have been constructed by a process of phenotypic modification by natural selection for a particular gene-propagating effect. [Gangestad and Scheyd 2005, 525]

Darwin saw how great it was for farmers to use selective breeding, but in nature, the strongest were led to propagate by being the ones to survive the harsh wilderness with limited resources. (Schoenberg 2022, Humans use selective breeding to generate the best crops while nature uses natural selection to ensure the strongest survive–humans do not procreate through natural selection, they have a choice in who they procreate with thus separating themselves from Darwin's observations.

When certain species are choosing a mate, sometimes they choose the mate that is the most beautiful, as opposed to the strongest–and sometimes the most beautiful can still be the strongest. Ferris Jabr explains how beauty traits have been used by the flame bowerbird which has a flame-like incandescent plumage, the male peacock with its grandiose display of colorful and large tail feathers, or the male swordtail's long yellow striped reflective tail (Jabr 1,7). This disposition to finding the most beautiful trait is referred to as sexual selection, and according to Schoenberg it “has been used to explain why humans have big butts” (Schoenberg 2022, Not all beautiful traits are only beautiful though, some do offer an evolutionary advantage. Selecting a mate with a big butt is sexual selection, but from a natural selection standpoint, the fat around a big butt is “high in omega-3 acids, which promote brain growth, while fat stored around the middle is loaded with omega-6 acids” (Davenport 2021). Through sexual selection, women have evolved to have larger butts, because “men are attracted to women with an hourglass body shape, in the same way, that women like tall men with broad shoulders. In fact, it’s the number one characteristic that men are looking for in a woman” (Davenport 2021). In the animal kingdom these beautiful traits can make an animal more susceptible to a predator; in the human world being beautiful can help in several different ways:

The most astonishing results for humans include the following: (i) attractive persons are not only more popular with the other sex, but they are also more successful in their professional careers, i.e., they achieve better grades in school and receive higher salaries in their later vocations. [Rusch & Voland 2013,116]

Within the human population, there is one major beauty trait that is noticed immediately upon seeing one another, race–even with races' biological insignificance, humans cannot help but categorize others by skin color. When Ann Gibbon spoke with evolutionary geneticist Sarah Tishkoff she said, “You can’t use skin color to classify humans, any more than you can use other complex traits like height, Tishkoff says” (Gibbons 2017). Schoenberg supports this view:" the decision to group people based on superficial visual characteristics is not founded in absolute biological difference, but in a long history of cultural difference. Race is culture, not biology. We have a cultural tendency to cram human variation into racial categories" (Schoenberg 2021, 7.4).

Within the continent of Africa, skin color can range from the deepest of blacks to beige. These African genes can also be seen in some Pacific Islanders, Eurasia, and mutated versions gave Europeans their lighter skin color (Gibbons 2017). Darker skin is able to protect the body better from harmful UV radiation, so “when humans migrated out of Africa and headed to the far north, they evolved lighter skin as an adaptation to limited sunlight. (Pale skin synthesizes more vitamin D when light is scarce)” (Gibbons 2017). Over the last 6000 years a gene has swept through European populations that caused a lighter skin color; the “depigmentation gene,” also referred to as SLC24A5 (Gibbons 2017). Both Gibbons and Schoenberg see the flaws in categorizing humans by skin color, and Gibbons gives evidence that African genes can be found around the world.

From an evolutionary standpoint, darker skin offers more protection from the sun, but unfortunately, beauty standards in the 1960s told black women that they needed straight hair, light skin, and thin lips. Beauty standards had such a white, European ideal that “there were quite a few girls who tried to bleach their skin white with bleaching cream” (Baird 2021). Black women were being told that their own natural beauty–curly hair, big lips, and dark skin–was inferior and they had to adopt the more traditional white standard of beauty (Baird 2021). Baird discusses the Civil Rights Movement of the 1960s which, “represented the rejection of Eurocentric, white models in favor of more Afrocentric and black norms” (Baird 2021).  Due to this rejection of Eurocentric beauty standards, cosmetics specifically for black women had a rapid increase in numbers (Baird 2021). The new spotlight of natural beauty also led to the afro-style of hair gaining popularity in the late 1960s–the phrase, “Black is Beautiful',' also became an empowering slogan to celebrate back skin and hair (Baird 2021). Rusch & Voland have established that people who are found to be beautiful have an easier time in life and Gibbons says that many “races” around the world share common skin color genes, but according to  Eric W. Cerrati and J. Regan Thomas, the four facial characteristics that equate to beauty are; symmetry, averageness, youthfulness, and sexual dimorphism (Cerrati & Thomas 2017).

Beauty standards have changed countless times over the years and they are continually evolving; there is no universally quantifiable beauty standard (Cerrati & Thomas 2017). Humans are attracted to beautiful people because, “beauty is perceived by humans as a sign of favorable genes and increased fertility”  (Cerrati & Thomas 2017). This is how Cerrati and Thomas explain the four facial characteristics:

The first concept of symmetry is believed to represent a high quality of development. A symmetric face reflects a person's phenotypic and genetic condition giving him or her an advantage in sexual competition. Averageness, the second concept, is informed by the Darwinian theory that evolutionary pressures function against the extremes of the population. As a result, humans innately appreciate that averageness represents genetic heterozygosity and a greater resistance to disease. The third concept is youthfulness. Neonatal features, such as large eyes and a small nose, are believed to suggest desirable qualities of youthful liveliness, open-mindedness and affability. As a person ages and demonstrates soft tissue descent, the face deviates from the phi standard, resulting in a decrease in attractiveness. In addition, the human brain interprets the physical changes of aging as a decrease in fertility. The fourth and last concept of beauty is sexual dimorphism, which is defined as a phenotypic difference between males and females. For females, increased estrogen leads to the development of secondary characteristics that suggest a fertile host and a reproductive advantage. These include a thin jaw, small chin, large widely spaced eyes, small nose, high cheekbones, and plump lips. On the contrary, desirable physical features in men are those that signify high testosterone levels, such as prominent chins, square jaws, deep-set eyes, thin lips, heavy brows and abundant hair. [Cerrati & Thomas 2017,1]

Baird discussed how black women were told, in the 1960s, that they needed to have thinner lips; but according to Cerrati and Thomas, plump lips could be an evolutionary trait that shows the bearer is more fertile. Facial structure offers a large degree of variation, and two of the main contributing factors are biological sex and race/ethnicity. In a study conducted by Ziqing Zhuang, Douglas Lansittel, Stacey Benson, Raymond Roberge, and Ronald Shaffer, it showed that African Americans tend to have shorter, wider, and shallower noses when compared to Caucasian people; when comparing Hispanics and Caucasians, the study showed that Hispanic's nose protrusion and head length are shorter; one last group that they looked at was the Asian community, people of Asian descent had many similarities with African Americans having larger faces and features ( Zhuang et al 2010). Gangestad and Scheyd further support Cerrati and Thomas’s declaration of desired facial aesthetics when they said, “men prefer female faces with relatively small chins, large eyes, high cheekbones, and full lips” (Gangestad & Scheyd 2005). The evolution of these traits can be carried on through sexual selection as described here:

Physical traits individuals are selected to find attractive may be thought of as signals of underlying qualities. The coevolution of preferences and preferred traits, then, can be thought of as the evolution of a signaling system, which entails that one sex (signalers) possess signals and the other sex (receivers) possess psychological (cognitive and motivational) capacities to perceive and act upon (e.g., be attracted to) those signals.[Gangestad, & Scheyd, G. J. 2005, 527]

Beautiful traits in humans have evolved alongside them with race. As humans migrated more north, from Africa, skin became lighter; and through selective breeding, humans have gone on to express traits that are, culturally, seen as beautiful. With this came larger butts for women, and prominent chins for men. Farmers have similarly used selective breeding to increase food size, taste, and output. Darwin recognized that through natural selection a species will evolve the strongest traits through procreation; in nature, the strongest survive. Sexual selection allows a species to choose a mate based on a beautiful trait–even at the detriment of the animal which makes it more susceptible to predation due to the extravagant displays. Over time these beautiful traits get grander and more vibrant because the chosen mate has the most colorful plumage or the biggest butt. These beautiful traits are thought to have a subconscious effect on a potential mate and these traits make them a strong mate. Though humans of all races can have any and all of the beautiful traits discussed, one classification that many anthropologists have determined to be ineffective at separating humans is race. Many genes for skin color originate in Africa, which gives many races a similar ancestor. Beauty will always be in the eye of the beholder, except for the four facial characteristics of symmetry, averageness, youthfulness, and sexual dimorphism. Humans love beautiful things because humans are beautiful.


Schoenberg, A. (2021). Introduction to Physical Anthropology. Retrieved April 2022, from https://arnieschoenberg.com/anth/bio/intro/index.html.

Gangestad, & Scheyd, G. J. (2005). The Evolution of Human Physical Attractiveness. Annual Review of Anthropology, 34(1), 523–548. https://doi.org/10.1146/annurev.anthro.33.070203.143733

Jabr, F. (2019). How Beauty Is Making Scientists Rethink Evolution. The New York Times Magazine.

Davenport, M. (2021, July 15). Defining the ideal female body shape. Barbell Therapy London. Retrieved May 6, 2022, from https://www.barbelltherapy.co.uk/2020/09/08/defining-the-ideal-female-body-shape/

Rusch, H., & Voland, E. (2013). Evolutionary aesthetics: An introduction to key concepts and current issues. Aisthesis. Pratiche, linguaggi e saperi dell'estetico. Retrieved April 15, 2022, from https://oajournals.fupress.net/index.php/aisthesis/article/view/674

Gibbons, Ann. “New Gene Variants Reveal the Evolution of Human Skin Color.” Science, 12 Oct. 2017, https://www.science.org/content/article/new-gene-variants-reveal-evolution-human-skin-color

Melissa L. Baird (2021) ‘Making Black More Beautiful’: Black Women and the Cosmetics Industry in the Post-Civil Rights Era. Retrieved May 6th 2022 from https://onlinelibrary.wiley.com/doi/full/10.1111/1468-0424.12522

Cerrati, E. W., & Thomas, J. R. (2017, July). “The multicultural evolution of beauty in Facial surgery&rdquot;. Brazilian Journal of Otorhinolaryngology. Retrieved April 12th, 2022. https://www.scielo.br/j/bjorl/a/kcGpvdbg9gdbs8m9FH5MHmc/?lang=en

Ziqing Zhuang, Douglas Landsittel, Stacey Benson, Raymond Roberge, Ronald Shaffer (June 2010). “Facial Anthropometric Differences among Gender, Ethnicity, and Age Groups”. The Annals of Occupational Hygiene. Volume 54, Issue 4, June 2010, Pages 391–402,          Retrieved May 6th,2022 https://academic.oup.com/annweh/article/54/4/391/273534

About the Author:

Abigail Fuentes-Cervantes: As for my educational goal, by next February I will be attending SDSU, where I will study administration of marketing and sales. It is taking me more time than I thought it was going to take me since I changed majors about a year and a half ago, and since my health recently got worse. But I know that if I keep up the good work and pass my classes I will be able to. Another educational goal is to work on my ADHD since I tend to struggle to concentrate, as well as find time to relax.

For my professional goal, once I graduate from SDSU, I want to keep working with the family business, but I would also like to open my own business or make it bigger than the one I already have. If everything turns out the way is going and my health is good I also want to enlist for a couple of years. Of course, once in a while, I would like to travel, and as I stated before, find time to relax, since life is so short and it moves too fast.

Michael Stewart is a lifelong learner who has been a licensed cosmetologist since March 2007 and has dedicated much of his professional life--eight years--to teaching at a local San Diego beauty school. After eight years of teaching almost every course available for him to teach, Michael now manages data for the same school and by doing so is able to help students across all campuses. Being a full-time employee and a full-time student leads to a busy life, but that is how true growth begins.

Academically Michael started his college experience at the ripe age of eighteen and dropped out at nineteen. Immediately after he attended Paul Mitchell the School San Diego. After a thirteen-year college hiatus, the COVID-19 pandemic led him back to his educational desires. Michael will begin taking courses at San Diego State University in the Fall of 2022 to complete a bachelor's in communications.

“Recognizing and Challenging Racism in Healthcare” by Maria Baez

The field of medicine is widely thought to be dedicated to the care of the sick without reservations and without judgment of patients. This much is interpreted through aspects such as the Hippocratic Oath, in which doctors swear to the proper care of any patients who seek their help. However, doctors are still human and, as such, there are issues and biases from human society that bleed into the field, regardless of intention; namely, racism. Medical racism is the discrimination of patients because of their race in the healthcare system, meaning that the quality and access to care unfairly favors white people over non-white people.

To understand medical racism, one must first understand racism and the concept of race itself. Through the study of biological anthropology, one can analyze why humans made this distinction in the first place. The origins of the concept of race are summarized in the following excerpt:

The decision to group people based on superficial visual characteristics is not founded in absolute biological difference, but in a long history of cultural difference …We look at skin color, body type, and facial features. These visual markers may seem critical to us, but they don't represent enough biological difference to separate people into significant groups. [Schoenberg 2021, 7.4]

While other forms of determining variance between humans have core biological distinctions, such as the differences between sexes, the concept of race has very little biological basis and is largely visual. To recognize visual distinctions and use the information to make judgments is not wholly unreasonable, given that this trait has been vital for human evolution and survival (Schoenberg 2021, 7.4). However, the issue lies in that, instead of judging color to determine the ripeness of a fruit, these visual judgments are being made about other humans, determining their worth to be different from other humans based on little more than melanin amount and cultures associated with it. Given the little biological justification for judging race, issues are bound to arise when it is allowed to influence a field so deeply ingrained in biology as medicine.

Medical racism, as previously mentioned, is when people are discriminated against for their race within the medical field, oftentimes influencing the quality of care they receive. Historically, this concept has gone beyond the quality of care and has many times been in the realm of specifically targeting racial minorities and causing irreversible damage to their communities. Oftentimes, this issue impacts African?Black and Indigenous Americans more severely than other racial groups. This was seen at the beginning of the United States’ conception with smallpox blankets given to Indigenous tribes and later on with inhumane testing on African-American communities. One of many instances of African?Black Americans having been mistreated as test subjects for healthcare was the Tuskegee Study of 1932, in which 600 Black men were monitored for 40 years to study syphilis without proof of informed consent from the participants. Larry Dossey, MD, explains this study in his article titled “Medical Racism”:

However, even when penicillin became the standard treatment for syphilis in 1947, researchers withheld the use of the antibiotic on these men in order to track the course of the untreated disease. By the end of the study in the early 1970s, not only had dozens of them died, but they had infected their spouses, sexual partners, and children with syphilis as well. [Dossey 2015, 167].

Dossey’s article details other events, in which primarily AfricanBlack Americans were illegally experimented on in the name of medical research, such as mass intentional infections and experiments involving patients being injected with plutonium (Dossey 2015, 168). Beyond such experimentations and studies, Dossey includes the eugenicist sterilizations forced on thousands of Americans. From 1927 to the 1970s, "around 65,000 Americans—mostly women and disproportionately black—were sterilized without their consent" (Dossey 2015,169) under the idea that the "genetically unfit" should not reproduce. Aligned with this notion, 25-50% of Indigenous American women were forcefully sterilized by America’s Indian Health Service from 1970 to 1976 under the threat of losing future welfare, healthcare, or even their children (Dossey 2015, 171). Woven in these instances and many more have been a baseline of eugenics, in which racist ideology was considered scientific fact. Namely, those who were “not desirable" (e.g. non-white, uneducated, disabled) were considered inferior and should be eliminated. Schoenberg describes eugenics briefly in his textbook:

Eugenics is the application of racist ideas to public policy. We blame Hitler for the most horrible atrocity in history while striving to create the master race, but many of his ideas came from the eugenics movement in the United States. The history of racism in the US goes back hundreds of years, and we have only just begun to dismantle racism [Schoenberg 2022, 7.4.1.]

This quote demonstrates the sheer influence of eugenics on not only the United States and its citizens, but how it has influenced the world as a whole through the mass genocide perpetrated by Adolf Hitler. As time has passed, eugenics has since been recognized as pseudoscience and largely denounced, but the pain it has caused is irreversible for countless people. Its influence has trickled down into the misconceptions and stereotypes that fuel medical racism in the modern-day.

The consequences of this phenomenon on people in the modern-day are vast and expansive, but Dayna Bowen Matthew summarizes it well in her book Just Medicine: A Cure for Racial Inequality in American Health Care: "Black and brown patients consistently receive inferior medical treatment ... in nearly every ... form of medical care than their white counterparts. Yet minority patients are sicker and more likely to die than whites from a wide range of diseases and illnesses for which we have data" (Matthew 2015, 1).  The effects are not only through the quality of care, but also emotional reactions to how patients are treated based on their race, as shown in a study titled “Race Matters: Perceptions of Race and Racism in a Sickle Cell Center” done by Stephen C. Nelson, MD and Heather W. Hackman, EdD. In a survey pool of 112 sickle cell anemia patients, 92.6% of whom identified as black, more than half of the surveyed individuals responded saying that they have experienced an emotional response because of treatment based on their race at this care center. Additionally, approximately half of that group responded by saying that the emotional responses were caused every time they visited. At times, some people go so far as to avoid medical care altogether, even for very serious medical issues, to prevent being potentially discriminated against or given inadequate care (Dossey 2015, 165). These effects each cause needless suffering on the part of the patient, whether physical or mental, in a way that they cannot control. Given that the whole purpose of healthcare is to relieve patients’ suffering, it stands to reason that an issue exacerbating that pain should not be tolerated. To go about extracting this discrimination from the system, one must know from what it originates.

The concept of medical racism does not mean that all healthcare workers intentionally discriminate against non-white patients. On the contrary, “health inequality in America is not the result of what doctors consciously think about race or minority patients. Instead, the phenomenon of unconscious bias is the virulent driver of the thinking, behavior, and interactions that produce health disparities” (Matthew 2015, 33). Since this issue is, for the most part, the result of implicit bias, going about a solution begins with confronting it and acknowledging that it exists. In Matthew’s words, “The importance of understanding that implicit biases are malleable cannot be overstated” (Matthew 2015, 157). As such, these biases can be adjusted and altered when presented with new information and inputs over time. The following are different strategies to curb these biases, one from Quinn Capers IV, MD et al. from their article “Bias and Racism Teaching Rounds at an Academic Medical Center” and Dayna Bowen Matthew's plans A, B, and C. The first is recurring moderated group discussions with healthcare employees and a facilitator reviewing their recent cases in depth, assessing if racial biases played a role in them and strategies to avoid similar events (Capers IV et al 2020, 5). In this environment, staff can review what went wrong, what assumptions and judgments were made, and then go through a process of developing plans within the group to circumvent the issues presented. Matthew’s methods of change are individual-based rather than group-based and are each dependent on where they occur in a sequence of events surrounding the activation of one’s biases. Matthew’s Type A is "Stereotype negotiation training", in which each individual actively and repetitively trains themselves to "denounce stereotypes and replace old automatic attitudes with newly learned ones" (Matthew 2015, 161). This type is meant to intervene both before stereotypes are activated and before implicit biases are formed, not allowing racial stereotypes perpetuated by society to take hold of their perception. Her Type B is "Promoting Counter-Stereotypes" after stereotypes are activated and before implicit biases are formed, in which individuals repeatedly see real-life examples that negate stereotypes, such as "famous and admired blacks ... and disliked whites" (Matthew 2015, 162). Lastly, her Type C, "Social and Self-Motivation", after both stereotype activation and implicit bias formation, is where the individual changes based on social consensus and how they are seen by others. For example, someone inhibiting automatic stereotypes for the sake of having a positive self-image when they discover those stereotypes are being used to discredit them (Matthew 2015, 165). While the first plan is specifically for healthcare settings, the ones provided by Matthew are dependent on each individual’s effort to change, making them general enough for anyone to use on their own. To spread these strategies, I have utilized a method of anthropology known as applied anthropology.

Applied anthropology is where anthropological theory is used for solving modern human issues. Seeing racism as a whole is an issue derived from collective human thought, it would be beneficial to use anthropology to explain it and hopefully minimize its damage. Applied anthropology can be utilized in a variety of forms, but the way I decided to present this information is one suited to my current skill set in visual media, which is a brochure. The inside of the brochure (Appendix A) contains less information than its outside counterpart, providing a definition and historical examples of medical racism. The left column acts as a subtitle describing what the next section, the middle column, is about. The right column serves the same purpose as the left, however, the sections it is introducing are on the back of the brochure. The back of the brochure (Appendix B) consists of more information on the effects of medical racism in the modern-day as well as approaches to tackling the issue. When complete, the right column would act as the cover of the brochure, depicting the title it shares with this essay. The middle column contains both information and works cited, as it would be the back of the brochure when folded. The leftmost column on this image would be seen folded inward when opening the brochure, with the right column resting on top of it. My color choices were made primarily with legibility in mind through color contrast, but also simultaneously reflect the medical theme. The background of the columns is a near-black purple color and a dark blue color, providing high contrast to the lighter colors of the text. Aside from their hue contrast to each other, the light blue and red colors for the text were each chosen due to their association with hospitals and medicine: blue corresponds to hospital gowns and nurses’ scrubs, and red represents the color of many first aid kits and most notably the symbol of the Red Cross. As for my images, I chose two depicting people and two without, all of which represent healthcare in some way. The first two, seen in Appendix B, depict a patient with brown skin wearing a hospital gown. On the brochure cover, they are seen alone and on the “Modern Day” section, they are seen with a nurse. In each image, the faces are cropped out. This cropping was a conscious decision, meant to represent how, in the face of racial biases, oftentimes those with darker skin are reduced to their skin color alone rather than being seen as an individual. The cropping of the nurse’s face was intentional as well. It represents how, due to the nature of implicit biases, the staff perpetuating biases onto patients could be just about anyone, regardless of intention. The other two images, seen in Appendix A, do not have such underlying meanings. They are of an empty hospital room and a doctor’s stethoscope, respectively, and are meant to portray the theme of healthcare, while also providing visual correlation with the blue and white colors of the text. The text itself is meant to inform not only people involved in the healthcare system but also anyone who does not realize the prevalence of this issue. Although the space to work with was limited, I tried to provide enough information to work with so that it may be a brief but informative introduction to medical racism, as well as including tactics from other sources that anyone with an open mind, medical staff or not, could incorporate into their daily lives.


Capers Q IV, Bond DA, Nori. “US, Bias and Racism Teaching Rounds at an Academic Medical Center”.CHEST (2020), https://doi.org/10.1016/j.chest.2020.08.2073.

Dossey, L. (2015). “Medical racism”. EXPLORE, 11(3), 165–174. https://doi.org/10.1016/j.explore.2015.02.009123.

Matthew, D. B. Just Medicine : A Cure for Racial Inequality in American Health Care. NYU Press, 2015.

Nelson, S. C., & Hackman, H. W. (2012). “Race matters: Perceptions of race and racism in a sickle cell center”. Pediatric Blood & Cancer, 60(3), 451–454. https://doi.org/10.1002/pbc.24361

Schoenberg, A. (2022). Introduction to Physical Anthropology.  https://arnieschoenberg.com/anth/bio/intro/index.html

Appendix A, Brochure

3 panel inside of brochure on Medical Racism, shows medical equipment and text Medical Racism Defined, Historical Examples

This image, when the brochure is fully printed and folded into thirds, would comprise the inside of the brochure.

3 panel outside of brochure on Medical Racism, shows people interacting and waiting in blue scrubs and text about: Modern Day, Solving the Problem, Sources, Recognizing and Challenging Racism in Healthcare

This image, when fully printed and folded into thirds, would comprise the outside of the brochure and would be printed on the other side of the first image.

About the Author:

Maria Baez is a student of San Diego City College, currently in her third year, after taking a semester-long break. They have been struggling to pinpoint an academic focus, mostly unsure due to varying interests. The global pandemic has also presented difficulties in learning that they had not previously had to face. Regardless, the one certainty is that they wish to finish school and improve their ability to learn, even if it takes longer than anticipated.

“Evolution’s effects on the flight deck: Orientation and Relative Movement” by Stephen Wortham

Aviation is something everyone’s probably seen and experienced in their lifetime within modern times. It’s a field very quickly making technological breakthroughs, yet we’re only just making strides as to how our land-based bodies themselves are affected by flight. One such concept that’s important to understand and look into is just how our bodies negatively react to flying. Due to the way our bodies have evolved, we perceive illusions of false movement. One such system in our body that is involved in a lot of these cases is called the Vestibular system. The important question is why does the vestibular system affect us so much in flight? Compared to other primates, how does ours differ, and why did it evolve this way? To answer these questions, I looked at numerous scientific articles revolving around the Vestibular system, its evolution, its comparison with other primates, and why it affects us in space flight. For this literature review, I want to cover a wide range of info written in these articles of different institutions, to see if we can answer our topic questions. I want to also make sure we cover the big picture: how our perception of movement and orientation was affected by evolution. I will cover a summary, analyze and compare our sources, synthesize and connect different articles' information, and finally bring it back to our main topic of how our evolution leads us to perceive orientation and relative movement within the spectrum of aviation.

To start, I want to introduce, “The evolution of the vestibular apparatus in apes and humans'', by Alessandro Urciuoli et al. The article is a recent publication that provides a new look into the detailed and complex findings behind the evolutionary changes of the vestibular system within extant primates like humans and apes compared to some extinct ancestors. This paper will provide much of the important and relevant information needed; revolving around what role the inner ear anatomy (vestibular system) plays in the phylogeny between extant hominoids (Humans, Monkeys, Apes) and extinct hominoids (Oreopithecus and Australopithecus) (Urciuoli 2020). Urciuoli, et al. asks the important question of whether this reconstruction can also help explain some of the complex and controversial phylogenetic relationships between fossils and history. In an attempt to answer that question, they create a phylogenetic reconstruction via 3D software and analysis of anthropoid ancestor fossils. They then quantify, compare, and test said phylogenetic signals with both extant anthropoids like Humans and Apes (Urciuoli 2020). But why is this important, especially to the focal point of this paper, aviation, and spatial awareness? It’s because the vestibular system is an extremely important part of how the human body maintains its balance and perception of orientation. As the United States Federal Aviation Administration puts it, “the vestibular system, which is also known as the organ of equilibrium” (Antunano 2005, 1). It contains two organs, the semicircular canals, referred to as “SC” containing a fluid called endolymph which detects angular acceleration, and the otolith organ, which detects vertical and lateral acceleration. As we can assume, these are extremely important when it comes to aviation operations, and understanding relative position in the sky. To relate this to our paper in question, the importance of comparing the shape and structure of the system to other primates in history could be very important clues that help us infer why our body’s equilibrium responds the way it does to certain stimuli in the aircraft. Through its complex usage of 3D imagery we’ll be able to not only conceptually, but visually put together a system and comparison as to why human’s organ of equilibrium evolved to the way it is. By reconstructing the taxonomy behind living primates, tracing their ancestors, and figuring out the dates as to when splits and differences happened, we are satisfying, “our main goal within Evolutionary systematics” (Schoenberg 2022, 5.1). For that, we have plenty of data gathered by Alessandro Urciuoli et al.; including comparisons in taxonomy between Homo sapiens, Pan troglodytes, Theropithecus gelada, and 13 other various primates. There is also plenty of supplemental material to go along with this.

To continue their investigations, Alessandro Uriciuoli et al took from a selected sample of a broad range of anthropoids and, in turn, introduced that to the 3D deformation software to get a highly detailed scan of the whole surface and shape. They then take the, “phylogenetically informative characters”, (Urciuoli 2020, Introduction) within their system and analyze them compared to the extinct anthropoid samples. Alessandro Urciuoli et al found that Anthropoid groups can be distinguished by the shape of the vestibular system’s variation. Through this, they were able to find key differences between such species as humans, great apes, and hylobatids. This then led them to conclude that the semicircular canal and its shape provide useful information for the phylogenetic signal. (Urciuoli 2020, Discussion) Not only does their methods of gathering data prove successful, but they end up uncovering quite useful and groundbreaking formation behind variations between different anthropoids’ system’s shapes and sizes, being noticeably different. The research conducted showcases that early models of the vestibular system in early ancestors were much more stout, and smaller than those in modern humans, which may prove interesting when we start synthesizing data. It’s also important to remember how the vestibular system is connected with spatial disorientation. As explained in the scientific journal, “Vestibular Illusions and Alterations in Aerospace Environment”, by Abdurrahman Engin Demir and Erdinç Aydın:

As the head is exposed to rotation with constant angular acceleration, the affected semicircular canals in the plane of the rotation begin to turn (Figure 2). At the very beginning of the turn, the canal walls also move in the same direction as the turn, but the endolymph itself lags behind due to inertia, then moves in the opposite direction of the turn and this fluid movement deflects the cupula to the same direction of the turn, causing a sensation of turning in the same way of the initial rotation. If this initial turn becomes prolonged with constant angular velocity for a period of 5–20 seconds, inertial endolymph flow ceases and can no longer generate a flow force to deflect the cupula. Within this period, the cupula gradually reverts to its central position because of its gelatinous structure, and no sensation of turning is perceived despite the persisting angular rotation. [Demir 2021, 1]

Overall, the vestibular system is a key factor in why we humans orient ourselves the way we do. It gives us a relative position on 3 planes of movement and provides us feedback on which way we’re facing. A major facet as to how we recognize that feedback so well is because of our cognition. We cannot look into why we are so affected by flight without looking at how we think the way we do. Quite possibly one of our most important traits, it helps with critical thinking and comprehension; two potential factors that are affected during spatial disorientation. Evolution of Primate Cognition, by Richard Byrne,is a book that offers insight into how our cognition developed by Byrne’s work to chart a tree of cognitive history within primates by “Comparative analysis of the behavior of modern primates, in conjunction with an accurate phylogenetic tree of relatedness” (Bryne 2010). The particular section we can focus on is Bryne’s section on Spatial Knowledge, where he goes into detail about the cognitive power it takes to be aware of the space around you. He uses the example of monkeys looking for a sparse food source in tropical forests. He says that by recognizing where the food source may be in the forest, the brain grows (Bryne 2010, 558). By not only looking at the physiological structures but also the psychological structures, we may be able to get a better picture of what’s exactly happening in cases of spatial disorientation and its connection to the vestibular system. One last source that could be useful for our synthesis is Primate Locomotion: Recent Advances by Elizabeth Strasser. It’s a collection of various articles and scientific readings that have been brought to organize a comprehensive reading on primate locomotion from the 1990s. I specifically want to cover Part 1, Chapter 5, “Locomotion, Support Use, Maintenance Activities, and Habitat Structure: The Case of the Tai Forest Cercopithecids”, as this chapter will help us understand the connections between cognitive behavior and its effect on movement by looking at monkey locomotion. With this in mind, we can now start putting together some of our sources to help digest our main article, and topic at hand.

Something interesting that repeats in a lot of the articles mentioned in the mention of size. One reference to this in The Evolution of the Vestibular Apparatus is:

cercopithecoids and hylobatids completely overlap due to the possession of slender SCs, while hominids as a whole (even if more markedly orangutans) differ by their swollen and relatively shorter SCs (with only a few cercopithecins falling within the hominid range). This might be related to the fact that hylobatids and cercopithecoids, unlike great apes, are swift-moving animals that make fast and large head movements, thus requiring a limited duct sensitivity to avoid overstimulation and a quick response to angular displacement (Spoor and Zonneveld 1998). [Urciuoli 2020, Discussion]

The size of the vestibular system matters and varies within different types of Anthropoids, the consensus being that based on the actions and regular behaviors and habits of the species, their semicircular canals and assumably otolith organs would either slim or grow stout, they may even extend or shrink in height. Another interesting fact gathered from the research article is the inference about overstimulation and quick responses. With the subjects' hylobatids (Gibbons) and cercopithecoids (Old world monkeys) being smaller and being faster moving for food and foraging, they required slender semicircular canals for rapid response to angular acceleration, and to avoid overstimulation which might lead to spatial disorientation. This is further backed by its connection to the brain, which also shows how the growth of the brain directly impacts its ability for spatial awareness and memorization of locomotive patterns. The paper itself agrees with this, stating that there are distinct patterns, and changes from our ancestors to us, specifically in the vertical semicircular canal, “related to the bipedal shuffling characteristic of this genus during foraging, causing them to spend an extremely large amount of time with an erect trunk posture” (Urciuoli 2020, Discussion). Bryne does argue that brain size does not entirely correlate with cognition, “Relative brain size is a good indication of the strength of the selection pressure promoting intelligence, because large brains are so costly, but maybe a poor index of what cognitive activity the brain allows” (Byrne 210, 558). However, it’s not just the size of the brain we are interested in, but the vestibular system and body itself. As mentioned within Primate Locomotion, “...(a small monkey) can travel on different supports in different forest types while still using the same locomotor behaviors. Taken together, these results certainly argue for the conservative nature of locomotion…” (Strasser 1999, 89).

Given the context and the excellent information we’ve gathered from our paper, we can finally start to theorize as to why our vestibular system affects us so much, and how it compares to other primates. Given our history of evolution, we grew to maintain a vertical posture and bipedalism, a move which may have required us to grow our vestibular system vertically. Human Bipedalism is often suggested to be a logical extension of the continuation of primates; due to the nature of primate’s vertical orientation. (Schoenberg 2022, 5.2.1). We also grew larger, not just in brain size but body size as well. As we can infer from the readings, this size in growth meant that we needed to worry more about our size relative to our movement in the world, leading to slower, more methodical movement, as inferred from Strasser. As we grew and mastered the art of bipedalism, our canals may have slimmed, but nowhere near to the extent of smaller, arboreal monkeys. We may hypothetically be less susceptible to spatial disorientation than our ancestors could have been, our bodies making tiny improvements to our equilibrium and the power of cognition making us aware of such things as spatial disorientation. But to conclude, we evolved to be ground-based, we are not an arboreal species that are used to the rapid movements in the air. This, in a sense, is what I think we can gather from our sources.

In conclusion, we’ve introduced the topic of the paper and established baseline information from the information we’ve been given from all of our sources, we were able to confidently  assess its legitimacy and postulate on potential ramifications it may have on other fields of study, like in this instance, Aviation. We’ve then gone into a discussion relating to the sources at hand, synthesizing them together to help answer our topic question. Although our postulation was rough, like in the words of Bryne, this is a paper that’s presented in the spirit of being an “edifice” to present current and recent findings (Bryne 2010, 562). Hopefully, these extremely important fields of research can later be compounded for more concrete and specific findings.


Urciuoli, Alessandro, et al. “The Evolution of the Vestibular Apparatus in Apes and Humans.” ELife, vol. 9, 2020, https://doi.org/10.7554/elife.51261.

Antunano, Melchor  J. “Spatial Disorientation.” Federal Aviation Administration, 10 May 2005.

Demir, Abdurrahman Engin, and Erdinç Aydın. “Vestibular Illusions and Alterations in Aerospace Environment.” Turkish Archives of Otorhinolaryngology, vol. 59, no. 2, 2021, pp. 139–149., doi:10.4274/tao.2021.2021-3-3.

Byrne, Richard W. “Evolution of Primate Cognition.” Cognitive Science, vol. 24, no. 3, 11 Feb. 2010, pp. 543–570., https://doi.org/10.1207/s15516709cog2403_8.

Strasser, Elizabeth. Primate Locomotion: Recent Advances. Plenum Press, 1999.

Schoenberg, Arnie 2022 Introduction to Physical Anthropology. https://arnieschoenberg.com/anth/bio/intro/index.html version: 17 March accessed: 17 March 2022

About the Author:

Hi, I'm Stephen Wortham, a second-year college student currently aiming for a degree in Aviation Science. After that, I hope to find an Aviation College like Embry-Riddle that will hopefully take me in. Although my goals aren't panning out as fast as I first thought, I'm slowly and surely making strides to get where I want to be; at the controls of a plane. I also hold an interest in some forms of art and meteorology and hope to maybe pursue some form of education in those aspects as well. I have not fully decided how I want to take my pilot aspirations, whether I join the military or find an airline. Like many things in life though, I have hope that the decision I make is not something I regret later on down the line.

“Human Health Effects of Genetically Modified Organisms” by Cory Horgan

Recent innovations in bioengineering and cultivation have made the utilization of Genetically Modified Organisms within the production of agriculture a very popular practice within modern society. These genetically modified organisms known commonly as GMOs allow for an increase in crop yields and reduced production costs (Powell 2015). Genetically altered organisms, although seemingly beneficial, have generated concern within various international health organizations among their possibly harmful effects upon humans. Although there have been over 100 large scale studies upon the short-term effects of GMOs, the lack of long-term studies upon their health hazards exposes possible issues such as human toxicity, negative effects upon offspring, and genetic variations which result from the consumption of these genetically modified organisms. (Celec 2005, 531) In response to these assertions, a variety of researchers have conducted experiments which seek to test the harmful long-term effects of GMO consumption.

To begin, GMOs are organisms which have a scientifically altered genome in order to express a desired trait (Schoenberg 2022, These organisms are constructed through a set strict set of scientific procedures which implement specific rDNA into various microorganisms, plants, and animals (Powell 2015). This process of genetically altering organisms is further analyzed by Chelsea Powell as she states

Genetically modified organisms (GMOs) are organisms that have been altered using genetic engineering methods. Although genetic engineering is a common and essential practice in biotechnology, its specific use in crops is controversial. The key steps involved in genetic engineering are identifying a trait of interest, isolating that trait, inserting that trait into a desired organism, and then propagating that organism. [Powell 2015]

The process allows researchers and farmers to generate altered variations of crops with greater yields, nutritional benefits, and reduced need for natural and artificial resources (Schoenberg 2022, In contrast to these societal benefits, social and scientific speculation among the integrity of various studies conducted by the Food and Drug Administration, have generated concern upon the human effects of GMOs (Celec 2005, 531).

After the initial implementation of GMOs into the United States, an organization known as the Institute for Responsible Technology conducted studies upon the effect of GMOs on mice. These studies found that genetically modified organisms negatively affected all organ systems and strongly cautioned against the human consumption of GMOs (Norris 2015). This study raised a variety of concerns among scientific and health researchers upon the possible risks of GMOs through the consumption of agriculture and different forms of produce. In continuation of these studies, various international research groups led by the National Institute of Toxicological Research in Seoul, Korea, conducted similar experiments upon the toxicity of GMOs (Alink 2008). This study initially conducted experiments similar to that of the institute for Responsible technology, by feeding genetically modified potatoes to mice over the course of a few weeks (Norris 2015). Following these studies scientists examined tissues extracted from the mice only to find that the tissue samples showed no differences from non-GMO fed mice. These results were expressed by Megan L. Norris' statement, “Histopathological examinations of the reproductive organs, liver, kidneys, and spleen showed no differences between GMO-eating and non-GMO-eating animals' ' (Norris 2015). These conflicting results generated a variety of other examinations held by international health groups and personal researchers such as Professor R. Casper who conducted further studies among sweet pepper and tomato plants which found conclusive evidence against the toxicity of GMO based crops. Further studies by large international groups over the next few decades such as the American Medical Association and World Health Organization found similar results that GMOs showed no level of toxicity upon the test subjects (Norris 2015). From these results researchers concluded that genetically modified organisms had no direct toxicity among studied all samples.

In continuation of concerns among the direct toxicity of GMOs, one additional health concern is the long term effects upon offspring which could arise from the consumption of GMOs. One hypothesis among modern health researchers was that the consumption of GMOs could generate complications of fertility, and possible genetic variations within offspring if consumed during the gestation period (Norris 2015). In response to these concerns researchers at South Dakota State University conducted experiments which analyzed the health conditions of GMO fed mice over the course of three generations. These scientists utilized a very common bacteria known as Bacillus thuringiensis which has been used in agricultural pesticides since the early 1960’s (Denise 2004). The researchers fed mice with corn sprayed with these common pesticides to see if there were any effects upon the fertility or genome of produced offspring. The methods behind these experiments included constantly feeding GMO corn-based meals which consisted of Bacillus thuringiensis bacteria (Denise 2004). They would then monitor the overall health and development of the mice over three generations of offspring. The researchers specifically monitored health upon all major organ systems with an emphasis on testicular development to ensure that no effects upon fertility were present. Over the course of the experiment researchers were able to find no data which indicated the fertility or genome of offspring was affected by GMO consumption. The data recorded found that no major changes in litter size, testicular development, or health of organ systems occurred over the course of all three generations of studied offspring (Denise 2004). In addition to these studies further examinations were conducted over five generations of offspring of various animals, expressing similar data in that no long-term effects were present over the course of multiple generations of offspring (Norris 2015). This data caused researchers to conclude that genetically modified organisms generate no effect upon the fertility or genetic variation of offspring.

One last public concern surrounding modern GMO’s is the direct genetic variations which can occur due to their consumption. These concerns are directly depicted by Megan L. Norris in her statement:

Concern has also surrounded the idea that genetically modified DNA would be unstable, causing damage (via unintentional mutations) not only to the crop, but also to whomever would consume it.  Mutations in DNA are closely tied to cancer and other diseases, and thus mutagenic substances can have dire effects on human health. The creation of mutations, called mutagenesis, can be measured and compared to known mutation-causing agents and known safe compounds, allowing researchers to determine whether drugs, chemicals, and foods cause increased mutation rates. [Norris 2015]

In order to test variations in genes due to GMO consumption the National Laboratory of Protein Engineering and Plant Genetic Engineering tested the mutation of mice genes caused by the consumption of proteins found within modern pesticides (Jonas 2001). Within this study, researchers systematically fed mice diets of GMO based corn and tomatoes consisting of coat proteins found within many modern-day pesticides (Norris 2015). Researchers closely monitored the mice for mutations which occurred throughout the experiment. Data within the experiment concluded that no direct mutations occurred within the mice due to GMO consumption (Jonas 2001). In addition, further studies utilized identical methods over the course of five generations of mice. These long-term studies were conducted to find if DNA transfer occurred due to GMO consumption which could later result in genetic variation. This study also found no indication of DNA transfer from genetically modified organisms within any of the five generations of mice studied (Jonas 2001). From both of these data sets researchers concluded that GMO’s do not cause genetic mutations or DNA transfer.

In conclusion, although there has been much public concern over the incorporation of GMOs into modern agriculture and produce. A variety of studies have concluded that GMOs have minimal negative effects upon animals and humans. These tests have concluded that GMOs generate no sign of toxicity for humans, effects upon offspring, or genetic mutation due to their consumption. This data has assured the overall safety upon GMO consumption and contributes to further research and advancements within bioengineering and agricultural cultivation.


EFSA GMO Panel Working Group on Animal Feeding Trials. 2008. Safety and nutritional assessment of GM plants and derived food and feed: The role of Animal Feeding Trials. Food and chemical toxicology British Industrial Biological Research Association. Retrieved May 24, 2022, from https://pubmed.ncbi.nlm.nih.gov/18328408/

Biomedicine & Pharmacotherapy. ScienceDirect.com by Elsevier. (n.d.). Retrieved May 24, 2022, from https://www.sciencedirect.com/journal/biomedicine-and-pharmacotherapy

Chen, Z.-L., Gu, H., Li, Y., Su, Y., Wu, P., Jiang, Z., Ming, X., Tian, J., Pan, N., & Qu, L.-J. (2003, May 7). "Safety assessment for genetically modified sweet pepper and Tomato". Toxicology. Retrieved May 24, 2022, from https://www.sciencedirect.com/science/article/pii/S0300483X03001112?via%3Dihub

Brake, Denise G, Robert Thaler, and Donald P Evenson. 2004. "Evaluation of bt (bacillus thuringiensis) corn on mouse testicular development by dual parameter flow cytometry". Journal of agricultural and food chemistry. Retrieved May 24, 2022, from https://pubmed.ncbi.nlm.nih.gov/15053558/

Jonas DA;Elmadfa I;Engel KH;Heller KJ;Kozianowski G;König A;Müller D;Narbonne JF;Wackernagel W;Kleiner J; (n.d.). "Safety considerations of DNA in food". Annals of nutrition & metabolism. Retrieved May 24, 2022, from https://pubmed.ncbi.nlm.nih.gov/11786646/

Norris,  Megan L.  (2021, January 17). "Will gmos hurt my body? the public's concerns and how scientists have addressed them". Science in the News. Retrieved May 24, 2022, from https://sitn.hms.harvard.edu/flash/2015/will-gmos-hurt-my-body/

 Powell, Chelsea. (2015, August 11). "How to make a GMO". Science in the News. Retrieved May 24, 2022, from https://sitn.hms.harvard.edu/flash/2015/how-to-make-a-gmo/

Niederhuber, Matthew. (2015, August 11). "Insecticidal plants: The tech and safety of GM Bt crops". Science in the News. Retrieved May 24, 2022, from https://sitn.hms.harvard.edu/flash/2015/insecticidal-plants/

About the Author:

Cory Horgan is a college student who will be transferring from San Diego Community College to San Diego State University in the fall of 2022. Cory is currently working towards a bachelor's degree in electrical engineering. With the completion of his bachelor's degree Cory aspires to work on electrical components under automotive or aviation companies, and possibly one day own his own electrical engineering company.

“Evolution of Oral Disease and Pathogens” by Angel Madrigal

Diseases have been plaguing mankind for ages, from the COVID-19 pandemic, to the Antonine plague in 165 AD, and while we hear about the plagues and pandemics often, on occasion we overlook dental/oral diseases that seem quite miniscule or even insignificant when we compare them to major diseases linked to historical epidemics. Diseases are constantly evolving and some even play important roles in human development and evolution (Schoenberg, 2022).  Like other diseases, oral diseases have long plagued humans as well, not just traditional viruses like HIV/AIDS and Herpes, but things like dental caries and periodontitis go back thousands of years. This paper will review the literature, present, and discuss concrete research regarding the subject of paleopathology, specifically research that investigates the evolution of dental caries and the bacteria that causes them. Dental caries have an interesting history and the bacteria that causes them plays a vital and destructive role in the human body. By presenting this information on oral bacteria, viruses, and pathogens, I would like to highlight the importance of oral paleopathology within Anthropology and Public Health.

Paleopathology attempts to study diseases of ancient populations and relates its findings to related disciplines which include dentistry and anthropology and of course a myriad of other subjects (Grauer 553). Dental Paleopathology likewise studies diseases relating to ancient populations but with a focus on dentistry, specifically teeth and jaws (Grauer 554). There are a few reasons why a proper understanding of paleopathology is important, specifically Anthropology. Evolution is an important subject within biological anthropology, studying older populations and comparing them to current information, data, and literature, regarding teeth and jaws in modern populations, there is a plethora of information we can uncover about the evolution within an area of the human body, it can also help us explain other phenomena within humans. Studying oral disease and pathogenic bacteria can give us insight into the evolution of the human immune system, seeing that there is a possibility that pathogenic bacteria (as well as nonpathogenic bacteria) can influence the development of the immune system (Foster et al 2018). Studying teeth and jaws and teeth of certain populations and eras can also reveal more than just health, it can also reveal socioeconomic status (Lacy 2014).  As well as being a great source for anthropology, studying ancient jaws and teeth also serves as a great source for public health experts looking for more insight into human health and oral health is a great indicator of overall health as well and bad oral health can serve as a sign of bad overall health (Lacy 2014).

 The earliest evidence of dental caries and periodontal disease we have is from the pleistocene epoch, about 1.1 to 4.4 million years ago (Lacy 2014). Previously it was thought that the increase of carbohydrate based diets after the discovery and use of agriculture was what caused a various amount of dental caries among Neolithic populations (Oxilia et al 2014). Although now we know that caries were prevalent in populations earlier than the Neolithic, it is still agreed upon that the rise of agriculture certainly caused a massive change in health for humans, orally and generally  (Lacy 2014, Oxilia et al 2014). The microbiome is a structure and combination that is made up of various bacteria, fungi, parasites, and viruses (Ursell et al 2013). The microbiome is an important part of the human body and plays a vital role in the human body being able to run smoothly and successfully (Ursell et al 2013). The oral microbiome is the second largest after the gut microbiome, it consists of about 700 different species of bacteria (Deo and Deshmukh 2019).  The microbiome is typically based on genetics and DNA, everyone has a “unique” set of bacterial combinations in their microbiome, typically passed down from a mom. With Streptococcus mutans and other forms of Streptococcus, they are typically passed down by direct physical contact with one's mother (Yates et al 2021) rather than being passed down through breast milk (Ursell et al 2013). Streptococcus, an early colonizer of the oral microbiome, saw an explosion and presumably began its colonization dominance when an increased consumption of carbohydrate rich and starchy foods began after the discovery of agriculture (Cornejo et al 2012).  Streptococcus, one of the most dominant bacteria in our oral microbiome and one the core bacterias that have been with us for almost 40 million years (Yates et al), has been the main cause of dental caries in modern humans and in older populations and societies (Cornejo et al 2012, Simon 2007). Streptococcus Mutans uses carbohydrates to create acids that cause tooth demineralization, of course with the consumption of grains and foods higher in sugars Streptococcus would thrive and it did at the advent of agriculture (Oxilia et al 2015). Streptococcus as a whole seems to be part of the balance within the human microbiome, including the oral microbiome (Baron 1996). This means that although streptococcus has destructive tendencies, it also plays an important role in the maintenance and balance of the oral (and overall) microbiome.

Although some oral pathogens such as herpes, HIV/AIDS, and Coxsackie virus, behave like traditional pathogens, research suggests that some more chronic oral diseases such as caries and periodontal disease are not pathogens in the traditional sense, rather their pathogenic-like behavior comes as a result of bacterial imbalance (Yates et al, 2021). This is important to note because studies regarding oral microbiomes of humans and other species, showed that the core microbiota in the oral microbiome of humans (or more broadly Homo) remain stable during times of dietary shifts throughout different time periods (Yates et al 2021 ). This supports the idea that caries was not only prevalent in post agricultural societies, it just happened more often because of the consumption of foods higher in sugars. Which would explain the discovery of higher caries prevalence in pre agricultural societies (Lacy, 2014). The failure to identify caries prevalence in older populations comes as a result of samples' high wear and the demineralization of the sample tooth fossils overtime as a result of calculus and preservation of caries (Lacy, 2014).

Indeed, Streptococcus was around and did cause caries in pre agricultural societies, the prevalence was higher than previously thought, though this idea alone is not very significant in the understanding of Streptococcus and its evolution. While we now know that Streptococcus is important to our oral microbiome, we also know that Streptococcus experienced a massive population increase at the dawn of agriculture and adapted a lot to the human dietary shift (Cornejo et al 2012). Although recent research concluded that oral microbiomes remained relatively stable throughout time and while humans underwent dietary shifts (Yates et al 2021), that research did not take in account individual bacteria and focused on populations of bacteria from a broader perspective rather than their evolution. With that being said, research suggests that agriculture did drive the dominance of cariogenic bacteria (that is bacteria that can cause dental caries) in the oral microbiome, changing the biodiversity of the mouth (Lacy 2014, Cornejo et al 2012). Though, the dominance of certain cariogenic bacterias such as S. mutans (Streptococcus) did not happen spontaneously, there were some obstacles that S. mutans had to face. “Among them, S. mutans needed to develop, or increase, efficiency in the metabolism of new sugars, successfully compete with bacterial species already present in the mouth of humans, develop defenses against increased oxidative stress, and resist the acidic by-products of its own new efficient carbohydrate metabolism” from Jacobson et al. 1989 (Cornejo et al 2012).

 Over time, S. mutans along with other cariogenic species would end up dominating the human oral microbiome and has been for the last few centuries (Lacy 2014).

Dental caries are not necessarily an mystery to the general population and especially not to scientists, while they are not a mystery to the general public, they are not necessarily down played but their importance is not necessarily stressed either, while we know why it is important to brush our teeth, it is typically not advertised why beyond the fact that it can cause dental caries and we’ll lose a tooth and what not. Simply put, it undermines the importance and complexity of a balanced oral microbiome. Aside from public health communication, dental research regarding older population is quite limited, despite most paleopathology research focusing on populations and before and during the rise of agriculture, rarely any dental paleopathology research has been conducted from the time period despite the amount of information it could reveal about diet, morbidity, age, interactions with others and environment, and overall health (Lacy 2014). These findings have the potential to reveal unknown information about humans. More specifically, focusing on the microbiome and its evolution, since we know that teeth have a lot to reveal about past populations, oral health, microbiome, and evolution through the formation of plaque and preservation of microbiomes and the various bacteria that make up these microbiomes (Yates et al 2021), we can uncover much more than we currently know about past populations.

Oral pathogens on the surface seem plain and basic but have a complex history and an extremely complex behavior. While they can be destructive in nature, they also play an important role in a healthy and balanced oral microbiome, they are part of the necessary bacterial combination that form the microbiome that indicate a healthy oral microbiome. In addition to playing an important role in the daily functions of the human body, the oral microbiome also plays a role in the development of the gut microbiome, in turn leading to the development of the immune system. The consistency of the combination of the bacteria belonging to the oral microbiome shows its prolonged history and continuous importance in our bodies. While there is still much to uncover in the world of dental paleopathology, most recent research regarding the microbiome, cariogenic bacteria, and dental disease seems to be heading in a good direction, hopefully paving the way for important discoveries about overall human health and human evolution.


Fellows Yates, J. A., Velsko, I. M., Aron, F., Posth, C., Hofman, C. A., Austin, R. M., Parker, C. E., Mann, A. E., Nägele, K., Arthur, K. W., Arthur, J. W., Bauer, C. C., Crevecoeur, I., Cupillard, C., Curtis, M. C., Dalén, L., Díaz-Zorita Bonilla, M., Díez Fernández-Lomana, J. C., Drucker, D. G., … Warinner, C. (2021). "The evolution and changing ecology of the african hominid oral microbiome." Proceedings of the National Academy of Sciences, 118(20). https://doi.org/10.1073/pnas.2021655118

Lacy, Sarah Ashlyn, "Oral Health and its Implications in Late Pleistocene Western Eurasian Humans" (2014). All Theses and Dissertations (ETDs). 1245. https://openscholarship.wustl.edu/etd/1245/

Oxilia, G., Peresani, M., Romandini, M. et al. Earliest evidence of dental caries manipulation in the Late Upper Paleolithic. Sci Rep 5, 12150 (2015). https://doi.org/10.1038/srep12150

Omar E. Cornejo, Tristan Lefébure, Paulina D. Pavinski Bitar, Ping Lang, Vincent P. Richards, Kirsten Eilertson, Thuy Do, David Beighton, Lin Zeng, Sang-Joon Ahn, Robert A. Burne, Adam Siepel, Carlos D. Bustamante, Michael J. Stanhope," Evolutionary and Population Genomics of the Cavity Causing Bacteria Streptococcus mutans", Molecular Biology and Evolution, Volume 30, Issue 4, April 2013, Pages 881–893, https://doi.org/10.1093/molbev/mss278

Deo, P. N., & Deshmukh, R. (2019). "Oral microbiome: Unveiling the fundamentals." Journal of oral and maxillofacial pathology. 23(1), 122–128. https://doi.org/10.4103/jomfp.JOMFP_304_18

Ursell, L. K., Metcalf, J. L., Parfrey, L. W., & Knight, R. (2012). "Defining the human microbiome." Nutrition reviews, 70 Suppl 1(Suppl 1), S38–S44. https://doi.org/10.1111/j.1753-4887.2012.00493.x

Baron S, editor. Medical Microbiology. 4th edition. Galveston (TX): University of Texas Medical Branch at Galveston; 1996. https://www.ncbi.nlm.nih.gov/books/NBK7627/

Foster, K. R., Schluter, J., Coyte, K. Z., & Rakoff-Nahoum, S. (2017). "The evolution of the host microbiome as an ecosystem on a leash." Nature, 548(7665), 43–51. https://doi.org/10.1038/nature23292

Gruader L., Anne. (2016). A Companion to Paleopathology.

Simon, Lisa. (2007). "The Role of Streptococcus Mutans And Oral Ecology in the Formation of Dental Caries." https://www.jyi.org/2007-december/2017/11/10/the-role-of-streptococcus-mutans-and-oral-ecology-in-the-formation-of-dental-caries

About the Author:

I am a 3rd year student at San Diego City College who is interested and enjoys studying a wide variety of academic subjects some of which include, history, philosophy, linguistics, physics, mathematics, anthropology, and many more.  I am currently majoring in mathematics and hope to transfer to UCSD in the near future. After my bachelors, I will hopefully pursue a masters degree.

“History and Summary of Xenotransplantation of Pig Organs to Humans” by Alex Pomeranz

Xenotransplantation, according to the United States Food and Drug Administration, is any procedure that involves the transplantation, implantation, or infusion into a human recipient of either live cells, tissues, or organs from a nonhuman source. This process is currently still somewhat of a medical fantasy, needing more research and development to make it a possible solution for the increasing demand for viable organs for those needing transplants. However, the idea of xenotransplantation has been around for centuries. In fact, the first documented use of the word ‘xenotransplantation’ can be dated back to 1667, during a discussion of transplanting lamb’s blood into humans (Tianyu 2020).

Even with its long history, xenotransplantation is as relevant in modern medicine as ever and is important to the study of anthropology. Biological or physical anthropology is the study of the biological and behavioral aspects of human beings, their extinct hominin ancestors, and related non-human primates, particularly from an evolutionary perspective. Xenotransplantation is especially possible in humans using their fellow primate relatives, such as baboons, for scientific and surgical trials. Humans, despite being the only bipedal primate, are very closely - in phylogenetic taxonomy - related to chimpanzees and bonobos (Schoenberg 2022, 5.3.1). Primates such as these are valued highly in many different fields of medical and scientific research because of their physiological closeness to that of humans, but still teeter on the fence concerning ethics. Xenotransplantation is a can of worms, ethically speaking, but it is considered one of the only possible solutions to solve the immense demand for transplantable organs for the human population. Because of their similarities to humans, other primates are test subjects instead of walking bags of adaptable organs. The organs themselves come from pigs, where their DNA has been genetically modified into being compatible with the immune system of that of a primate - baboons, chimpanzees, and potentially - eventually - humans. In a farm-to-table, no-waste sense, pig farming in this way is essentially the same as raising pigs to slaughter for meat-consumption purposes, so why not use the rest of it for the prosperity of human health? Pig organs are similar to human organs in shape and size, which make them a great candidate for transplantation, with the added bonus of their relatively large litter size, ease of breeding, and suitability for genetic engineering.

Genetically modifying the pig organs before transplant is the key to making the process of xenotransplantation work. Avoiding xenograft rejection has become one of the main goals on the way to making xenotransplantation a successful procedure. A type of xenograft rejection, hyperacute rejection, occurs when a wild-type pig organ is transplanted into a non-human primate and the transplanted graft radically becomes destroyed within minutes or hours. This occurs when the primate’s untreated antibodies react badly to the pig donor organ’s cells and rapidly reject the specimen for not being compatible, triggering complement proteins to start attacking the unfit structure. Hyperacute rejection can be avoided by preventing the formation of complement proteins and depleting pig antibodies in the recipient.

When transplanting nonhuman organs into human bodies, there is a large concern regarding the possible transmission of infectious agents or diseases from animal to human. This risk can be minimized by using a very controlled set of donor animals that have gone through an extensive genetic modification process, but the threat still lingers. However, not all of the viruses are entirely avoidable. The porcine endogenous retrovirus or PERV exists in all mammals and has the same reaction to genetically modified material as it does to organic DNA. There will always be a risk of transmission of the virus, but it is said to not replicate or cause disease under physiological conditions (Groth, 2007). Scientists soon became concerned about the transmission of this virus to humans. If the mostly dormant virus were to suddenly become pathogenic by being activated in the new bodily environment, the virus could subsequently be passed on to the patient’s doctors or caretakers, who then would pass it onto others, potentially sparking an epidemic. This fear has made the transplantation of cells or organs from pigs to humans a very dangerous idea, preventing the advancement of the xenotransplantation process as a whole.

Xenotransplantation as a modern medical procedure has been in the works for a very long time, despite major advancements only happening in recent years. The advantage of the gene-editing tool has revolutionized the procedure, but scientists and doctors alike have been trying to make xenotransplantation less of a fantasy and more of a reality since the early 1900s. Even before that, in 1838, the very first corneal transplant, from pig to human, was performed, yet human-to-human corneal transplants would not begin to regularly occur until 1905, 65 years later (Cooper 2015). Despite the early trials, xenotransplantation really began to advance beginning in the 1960s, when a scientist of Tulane University, Keith Reemtsma, hypothesized that primate kidneys could potentially function like that of human kidneys, effectively becoming a successful solution to renal failure (Cooper 2015). With very few viable kidneys for transplantation, either from alive or deceased humans, the procedure of transplanting chimpanzee kidneys into human recipients became a reality with a total of thirteen human patients receiving transplants. All but one of these transplant recipients lasted between four to eight weeks; the one other lasted nine months, with the patient even returning to work and normal life before suddenly collapsing and dying. The previous twelve patients all showed signs of organ rejection or infectious complication, but the thirteenth transplant still appeared to be healthy and functional during the post-death autopsy, showing no signs of acute or chronic rejection. The revolutionary advancements in xenotransplantation truly began in the 1980s, when Dr. David Cooper insisted that primate organs were not the best fit when transplanted into humans. Instead, Cooper hypothesized that pig organs were a near-perfect fit, considering their size and functionality. Despite this step forward, all of Cooper’s operations proved to be unsuccessful (Berki 2018). Regardless of the failures of clinical trials, scientists refused to give up and soon made more discoveries that would advance xenotransplantation globally, namely, the discovery of the main trigger of the human immune system: the sugar alpha-1,3-galactose on the surface of porcine cells (Berki, 2018). With this discovery in mind, advances were soon made to combat this trigger in the form of genetically modifying the pigs to be suitable for xenotransplantation, which were soon appropriately named “knockout pigs.” In 1992, another casualty helped scientists further study xenotransplantation when a Polish surgeon transplanted an unmodified pig heart into a human patient. The patient did not survive past another day and the death is generally attributed to the small size of the heart and its incompatibility to support the body’s circulatory system (PBS Frontline, 2014). Unfortunately, another major setback occurred soon after: the discovery of the Porcine Endogenous Retrovirus (PERV) instantly sparked fear of an epidemic among transplanted patients. By 1999, the United States Food and Drug Administration had banned the use of nonhuman primates in xenotransplantation, arguing that the risk of cross-species infection was too great. With animal activists protesting the procedures and trials in addition to the virus threat, most biotech companies that had been exploring the possibilities of xenotransplantation stopped their experiments and closed their labs by 2001 (Berki 2018).

Despite the series of unfortunate events befalling the scientific driving force behind xenotransplantation, the idea could never be forgotten when viewing the increasing need for viable, transplantable organs in a population of people who would die without one. One group of medical scientists found their opportunity to kickstart xenotransplantation into modern medicine on January 7, 2022. The opportunity to transplant a pig organ into a human with a chance to survive and recover was revolutionary, and the group of scientists at the University of Maryland Medical Center immediately jumped into action. The opportunity itself was unique, as the FDA had previously denied their request to begin performing clinical trials, citing their concerns about ensuring that the pigs came from a medical-grade facility and wanted the researchers to transplant the hearts into ten baboons before moving on to people (Reardon 2022). Despite this, their 57-year-old patient, David Bennet, allowed them to surpass the primate trials and experiment directly on him. Bennet had been on cardiac support after having been denied a medical heart pump due to his irregular heartbeat. Bennet had also been denied a human transplant because of his history of not following his doctors’ orders and treatment instructions. With no other option in sight to save his life, the FDA approved the xenotransplantation for this one time only (Reardon 2022). Despite the operation being a success and the transplanted heart showing no immediate signs of rejection, the patient, David Bennet, would only survive another month, and passed away on March 2, 2022. Shortly after, the University of Maryland Medical team and hospital spokesperson claimed that the cause of death was still unclear, but the findings being conducted are soon to be released in the physician team’s peer-reviewed medical journal. (Rabbin 2022). After reporting the death of Bennet, the New York Times stated, “The heart transplant was one of a number of pioneering procedures in recent months in which organs from genetically altered pigs were used to replace organs in humans… Mr. Bennett’s transplant was initially deemed successful. It is still considered a significant step forward because the pig’s heart was not immediately rejected and continued to function for well over a month, passing a critical milestone for transplant patients.” (Rabbin 2022).

As stated earlier, ethics concerning xenotransplantation is a can of worms, which, unfortunately, must be opened and discussed before xenotransplantation can continue in the medical science world. Opinions on the subject vary greatly, depending on whom you are inquiring. More religious people, and 75% of the United States public, insisted that the cloning of Dolly the sheep in 1996, was an abomination and the act of cloning itself was against God’s will. With that in mind, it was difficult for researchers to justify the procedures to them in the name of science (Rollin 2020). The fear of the dangers associated with genetic engineering, such as environmental dangers and the potential of a new pathogen, push scientists to answer to the public that risks are worth taking when the potential to save hundreds of thousands of human lives is on the line. The most difficult ethical issue to take into account on all sides is the effect of genetic engineering on the engineered animals and their current and future welfare. The animals’ welfare, of course, is always being directly pitted against the well-being of the humans involved, and historically, humans’ welfare has always won. Concerns for personal and public safety in regards to the xenotransplantation process also virtually eliminate medical privacy because a patient that has received a pig organ must submit to countless hours of testing to see if they have carried the PERV virus or a similar dangerous pathogen, in hopes of preventing the potential spread to others in the patient’s community. Thus, there arises an ethical tension between the good of the recipient and the good of society. (Rollin, 2020) The ethical issues regarding the animals themselves go beyond the genetic modifications and instead are rooted in the care and regard for the animal’s life itself. Pigs farmed for organ transplantation, even in a perfect world, could not roam freely in a pasture or pen like most animal-friendly farms have for hundreds of years. Instead, the pigs would have to be raised in a sterile, medically-heavy environment to ensure they are healthy enough for transplantation and to minimize the risks of a pathogen outbreak.

Most start to wonder here if that sort of environment would be suitable for the animal, even if it is genetically adapted to withstand it. “The concept of animal welfare is in part an ethical concept to which science brings relevant data. When we ask about an animal’s welfare, or about a person’s welfare, we are asking about what we owe the animal and to what extent.” (Rollin 2020) The U.S. agricultural community would answer that we owe the animal only what it takes to create profit. In cases of dogs and primates in captivity for scientific experiments, animal rights activists have advocated at the very least to partially accommodate their social, biological, and psychological natures. There is potential for an equilibrium to be found here, that accommodates the animals for a comfortable life and promotes new findings in the scientific community without their offices being burned down by radicalized activists, but only time and patience can bring this to reality.

In conclusion, xenotransplantation is one of the most revolutionary procedures and concepts that could potentially change medical science in its totality to improve and sustain human life. Without a viable answer to the ever-increasing demand for organs needed for transplant, the choices to solve the problem are limited and growing slimmer. The potential of xenotransplantation’s revolutionizing effects can only be discovered through further research and experimentation, when the Food and Drug Administration of the United States further permits it. Xenotransplantation would ultimately render the practice of using diseased or deceased organs entirely obsolete, taking with it all of the legal and practical issues that instantaneously are caused when harvesting organs from humans. With major steps forward, including the somewhat successful transplantation of a pig heart into patient David Bennet, the future of xenotransplantation is looking more promising than ever.


“A History of Xeno Experiments | Organ Farm | Frontline.” PBS, Public Broadcasting Service, 2014, https://www.pbs.org/wgbh/pages/frontline/shows/organfarm/etc/cron.html.

Berki, Dorottya M. “A Brief History of Xenotransplantation - Omixon: NGS for HLA.” Omixon, 17 Jan. 2018, https://www.omixon.com/brief-history-xenotransplantation/. 

Center for Biologics Evaluation and Research. “Xenotransplantation.” U.S. Food and Drug Administration, FDA, 3 Mar. 2021, https://www.fda.gov/vaccines-blood-biologics/xenotransplantation.

Cooper, David K C, et al. “A Brief History of Clinical Xenotransplantation.” International Journal of Surgery (London, England), U.S. National Library of Medicine, 26 June 2015, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4684730/. 

Groth, Carl G. “The Potential Advantages of Transplanting Organs from Pig to Man: A Transplant Surgeon's View.” Indian Journal of Urology. Medknow Publications, July 2007, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2721611/. 

Lu, Tianyu, et al. “Xenotransplantation: Current Status in Preclinical Research.” Frontiers, Frontiers in Immunology, 1 Jan. https://www.frontiersin.org/articles/10.3389/fimmu.2019.03060/full. 

Rabin, Roni Caryn. “Patient in Groundbreaking Heart Transplant Dies.” The New York Times, 9 Mar. 2022, https://www.nytimes.com/2022/03/09/health/heart-transplant-pig-bennett.html. 

Reardon, Sara. “First Pig-to-Human Heart Transplant: What Can Scientists Learn?” Nature News, Nature Publishing Group, 14 Jan. 2022, https://www.nature.com/articles/d41586-022-00111-9. 

Rollin, Bernard E. “Ethical and Societal Issues Occasioned by Xenotransplantation.” Animals: an Open Access Journal from MDPI, National Center for Biotechnology Information, 19 Sept. 2020, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7552641/.

About the Author

Alex Pomeranz is a student at San Diego City College with aspirations to transfer to NYU or St. John's University. With a lengthy background in journalism, Alex hopes to achieve a degree in creative writing as well as history. Thereafter, she plans on further pursuing education through law school and business school. Alex plans to one day own and operate her own law firm, but never plans on abandoning her love of writing.

“Can Man Pass Down the Intangible?” by Jontel Scott

At the core of every persons cells are the blueprint for how to function. This vital part of nearly all living organisms is called DNA. DNA can be thought of as what’s inside of the nucleus within your probably a trillion cells. Typically, most people are taught about how DNA controls the way that different parts of the body function at the cellular level. Your chromosomes direct protein synthesis, which determines how the cells interact with one another, and overall how individuals function (Schoenberg 2020, 2.4.1). Today, there are researchers who are attempting to explore how much of an impact that DNA has on the less tangible parts of who we are, like personality traits. The beginning of molecular genetic studies as it applies to the heritability of traits specifically, began in 1996. (Ebstein 2006, 1) But even before that, in the middle of the 20th century researchers had begun to use microscopes to outline the human genome. New alleles are discovered daily, and some even intentionally created” (Schoenberg 2020, 2.4). Researchers initially set out to understand the connection between the chemical dopamine and personality traits Novelty Seeking/Extraversion. Further understanding of this topic could have a significant impact on how society views the classic nurture vs nature debate. Even more, this type of research will have lasting change on how the medical field approaches mental health. Managing to better understand how genetics affects the intangible parts of who people are is bound to have a net positive effect on society as a whole.

These intangible things, like personality traits, are defined by the Research Domain Criteria (RDoC) as, the relatively enduring patterns of thoughts, feelings and behaviors that reflect the tendency to respond in certain ways under certain circumstances ” (Sanchez Roige). Relating to the impact on the mental health field, psychiatric diseases are characterized as extremes of normal tendencies including specific personality traits like neuroticism. Neuroticism, being an extreme emotional state of anxiousness or negative emotions can be linked to mental disorders that also show emotions in extreme states (Sanchez Roige). Just this one trait can also be linked to more general health risk outcomes like high BMI, smoking, and coronary artery disease (Sanchez Roige). It’s common knowledge that medicine today has treatments for mental illnesses like bipolar disorder or major depression. This medicine is just a combination of chemicals that are meant to target specific parts of a person's body in order to invoke a change that hopefully results in improved symptoms.

In order to understand the research around linking personality traits to people’s genes, it’s worth understanding the tools by which research is conducted. For a large majority of studies there is typically one of three, if not a combination, of the three types of self-reported questionnaires. The first being the Eysenck Personality Questionnaire (EPQ), which accounts for three specific traits of personality: psychoticism, extraversion, and neuroticism(Eysenck). This method has proven useful for researchers who need to administer a test that succinctly measures and gives insight into the personality of those taking the test (Eysenck). Second, another useful questionnaire is the Tridimensional Personality Questionnaire (TPQ). This method of questionnaire was initially tailored to focus more so on the biochemical bases of temperament. In this case, temperament accounted for traits like novelty seeking, harm avoidance, and reward dependence. Often associated with TPQ is the Temperament and Character Inventory (TCI). The TCI managed to include a fourth temperament, persistence. Also added were three other personality traits, self-directedness, cooperativeness, and self-transcendence. With the TPQ it was assumed that the inherited variations of temperament were influenced by monoamine neurotransmitter systems: serotonin for harm avoidance, dopamine for novelty seeking, and norepinephrine for reward dependence and persistence(Hamer). The final type of most commonly used questionnaires is the Five Factor model. The Five Factor model focuses on biological mechanisms that shape 5 distinctive traits, neuroticism, extraversion, openness to experience agreeableness, and conscientiousness. According to Sanchez-Roige, this is the most commonly used questionnaire for genetic studies. While not a questionnaire, the Biosocial model or theory, depending on the source, is also a useful tool for understanding how the biology of a person impacts their personality compared to environmental factors. In Journal of Personality Disorders by Dean Hamer, he states his understanding of the Biosocial model saying, “the biosocial model proposes that temperament involves differences in procedural memory, which is automatic and therefore presumably innate, whereas character develops from changes in propositional memory, which is the system used to learn goals and values through socialization and experience and therefore should be more environmentally influenced”. The Biosocial model differs from the questionnaires in that while it does give credit to biological factors, such as genes, it equally weighs the importance of environmental factors on a person’s likelihood to display certain personality traits. All of these methods are simply a means to gather and understand the relationship between a person’s biology and their personality. There are several other means by which researchers have used these methods to gain further insight.

For the sake of continuing our further understanding of the research, it’s important to examine how researchers approach conducting their experiments in the first place. Initial research in the field was conducted through the use of twin and family studies. Research began with this type of sample group because it was believed that twin and family studies would offer the most insight into what traits can be linked to heritability. A common issue drawn from these studies is  because of the nature of the sample size, the ability to conduct research on large same sizes was limited initially. Another common critique of twin studies is to what degree environmental factors play a part in the increase or decrease of genetic factors. This is overcome by most studies today due to the availability of larger sample size data. For example, “a meta-analysis of data from over 29,000 twin pairs showed that the heritability of neuroticism scores was at 48%, and that the same proportion of variance in neuroticism can be attributed to genetic factors in both in men and women (Sanchez Roige)”. Twin studies of personality have continued to yield important insight even in recent years. The next improvement to furthering research in the field was candidate gene studies. Candidate gene studies put special emphasis on the selection of genes that have been in some way related to the disease previously and offer prior knowledge about gene function (Patnala). Typically, in order to successfully use this method, researchers must first decide on specific genes as they relate to certain personality traits. The genes chosen are often associated with what’s called Single Nucleotide Polymorphism (SNP). These SNPs are a combination of the things that make up the individual parts of DNA. In Candidate Gene Studies specific SNPs are linked to personality traits or mental diseases. The isolation of these specific SNPs make it possible to associate a particular behavior trait with the SNP. For most studies that are accepted by fellow researchers, the specific SNP is usually cross referenced across already pre-established findings. This makes the knowledge derived from candidate gene studies valuable and clinically relevant as a potential disease diagnostic tool and for personalized medicine initiatives in future treatments of genetic disorders (Patnala). One of the criticisms of Candidate Gene Studies is the sample size used in many studies. Genome Wide Association Studies(GWAS) make up for this by using data from hundreds of thousands to millions of SNPs across the human genome. By not focusing on specific SNPs like Candidate Gene Studies, GWAS allow for a more robust understanding of which SNPs show repeated likelihood to influence certain personality traits or temperaments. Adding to the validity of GWAS is that normally the individuals being studied are unrelated, unlike what is usually seen in familial or twin studies. Another important point of GWAS is that its threshold for yielding significant findings is based on a Bonferroni correction for 1 million comparisons, yielding a threshold of P < 5.0 × 10−8(Sanchez‐Roige). Essentially, this just means that larger sample sizes are required to deduce significant findings amongst certain SNPs and the effect they have on the possibility of being present in different people. While early familial and twin studies used sample sizes in the hundreds, early GWAS started with sample sizes in the range of 1000 to 5000 subjects. Some studies have found GWAS helpful in genetic variations that contribute to common, complex diseases, such as asthma, cancer, diabetes, heart disease and mental illnesses(Genome). One of the things that have made GWAS much more useful is the completion of databases like the Human Genome Project in 2003 and the International HapMap Project in 2005. Other important databases include sources like the GPC, UK Biobank, 23andMe, Inc. and deCode Genetics. It’s important to note that these databases are only some of the many resources used by researchers that contain data from individuals who have answered some version of a questionnaire to aid in the further understanding of genes and their correlation to personality traits and mental disorders.

The Five-Factor Model of Personality serves as another robust method for conducting research studies. “The five-factor model was developed in the 1980s and ’90s largely on the basis of the lexical hypothesis, which suggested that the fundamental traits of human personality have, over time, become encoded in language” (Britannica). With this method personality traits are understood as patterns of thought, feeling, and behavior that are relatively enduring across an individual’s life span(Britannica). The personality traits associated with this model are extraversion, neuroticism, openness to experience, agreeableness, and conscientiousness. It has proven satisfactory as a tool for studying genetic mapping for three specific reasons according to Brittannica, “First, the five factors have consistently emerged from factor analyses conducted on numerous data sets composed of descriptive trait terms from a number of languages, including English, Chinese, and German. Second, twin and adoption studies have revealed a substantial genetic component to the five factors. Third, the five factors have been applied across the human lifespan”. Its standing for use is strengthened by the usefulness that it has contributed to fields such as social, clinical, and industrial-organizational domains (Britannica). Another helpful tool for understanding the research is genomic Profile Risk Scoring (PRS). This method is used for investigating the polygenic nature of traits like personality and can also be used to explore the genetic basis of correlations between traits like personality and psychopathology (Britannica). These methods are the ones through which one can ascertain a more comprehensive understanding of what personality traits are and their connections.

It seems fitting to start the exploration into these personality traits and their connections with one of the most studied and correlated traits, neuroticism. This trait is best generally characterized by those who see the world as distressing, threatening, and unsafe. The trait definitely operates on a spectrum with people that fall across a wide spectrum. Some will be highly neurotic and may exhibit ever changing emotions, anxiousness, withdrawn tendencies and a tense disposition. Inversely, those who show low neurotic tendencies seem to be content, confident, and stable. According to Sanchez‐Roige there is also a supported link between neuroticism and mental disorders such as major depressive disorder, bipolar disorder, and other anxiety based disorders. When it comes to the EPQ, neuroticism is understood by a means of emotional stability. As for the Five Factor model, neuroticism stood out along with two other traits, extraversion and psychoticism, as being especially useful in gene studies(Britannica). This model correlates it to emotional instability, irritableness, and moody behavior. Beyond the mind, neuroticism has also been linked to more general health risk outcomes including high BMI, smoking, and coronary artery disease (Nature). That early research in 1996 saw fit to further investigate the linkage between neuroticism and the gene associated with the serotonin transporter SLC6A4 (Ebstein). This serotonin transporter gene is of particular interest in genetic studies because it is believed that the primary purpose of this gene is to influence mood regulation and the degree to which serotonin is absorbed by cultured cells, platelets, and the brain (Hamer). Based on two studies with a sample size of 902 participants, research has suggested that when there is a poorly transcribed short form of the polymorphism that is associated with the serotonin transporter gene that the degree to which a person displays signs of neuroticism can be affected. The data suggests that when a person is more likely to be neurotic and less likely to be agreeable. This gene is only one of the many SNPs associated with neuroticism. Across so many different testing methods, neuroticism has repeatedly shown up, offering high suggestibility that it is a genetically inheritable trait.

The next most researched trait amongst several testing methods is extraversion. This trait is believed to be characterized by the tendency to experience positive emotions, to be active and feel energetic, to be talkative and to enjoy social interactions (van den Berg). Researchers have also observed that those high in respect to extraversion display increased assertive, energetic, and gregarious behaviors (Grice). Unlike neuroticism, the lifestyle markers for those who strongly show signs of extraversion are numerous psychosocial, lifestyle and health outcomes, such as academic and job performance, well-being, obesity, substance use, physical activity, bipolar disorder, borderline personality disorder, ADHD, Alzheimer’s disease, and longevity (Sanchez Roige). The current belief is that extraversion becomes more stable genetically when a person is in adolescence. By the time adulthood is reached the extent to which extraversion is perfectly genetically stable is reached. It is a critical part of the Five Factor Model. It also has been tested against large sample sizes up to 63,000 with positive results showing possibility for heritability. Early research reported associations between SNPs in the gene that is associated with dopamine receptors DDR4 and novelty seeking. Like many of the different personality traits and temperaments, extraversion’s inheritability is very much considered to be polygenic. As of the most recent research there is no one gene or SNP that can be said to mark the guaranteed appearance of extraversion or to what extent.

“No single gene is believed responsible for any one of these traits. Instead, each trait, the Minnesota researchers propose, is determined by a great number of genes in combination, so that the pattern of inheritance is complex and indirect(Goleman 1986)”. The previously mentioned personality traits are only two of many other thoroughly researched traits and temperaments that are studied within this field.  By many accounts such as Sanchez-Roige, Hamer, Goleman, and many others the thing that these two traits and others like them have in common is that they are all considered to be polygenic in nature. This makes mapping the heritability of any trait extremely complex. Some of the other traits and temperaments include openness to experience, agreeableness, conscientiousness, cooperativeness, self-directedness, psychoticism, novelty seeking, harm avoidance(1), reward dependence, persistence, self-transcendence, Openness to Experience, agreeableness, and conscientiousness all fall under the Five Factor model. With this model openness to experience is characterized by an individual’s inquisitiveness, thoughtfulness and propensity for intellectually challenging tasks(Sanchez Roige). Agreeableness is identified by the Five Factor model as being empathic, sympathetic, and kind generally speaking. Conscientiousness has been referred to as an individual’s sense of responsibility and duty as well as foresight (Britannica). Traits and temperaments like persistence, self-directedness, cooperativeness, and self transcendence are most heavily associated with the Temperament and Character Inventory (TCI) method for researching the correlation between traits and genes. Individuals whose genes encourage cooperativeness have a strong correlation to reward dependence and harm avoidance according to Hamer. The TCI understands persistence as the ability to persevere in spite of fatigue or frustration. It sees self-directedness as the ability to modify behavior in order to achieve personal goals. Lastly, self transcendence is associated with experiencing spiritual aspects of the self.

In conclusion, the field of genetically mapping the correlation between the human genome and personality traits is ever changing. As data within the field increases it can be expected that researchers' understanding of this topic will understandably shift accordingly. Factors that complicate studies are the polygenic nature of personality traits across DNA. Polygenic means, “determined by a combination of many genes” (Schoenberg 2020, Research over the last few decades leaves plenty of further investigation into this field. From the very first twin studies, which offered valuable insight into the possibility of heritability of personality traits. Continuing into recent GWAS that access traits over large sample sizes to reveal more concrete analysis of how peoples’ genes have an impact on who they are. It goes without saying that the importance of further research in this field has the potential to revolutionize several different fields besides its own, including psychiatry, clinical psychology, and medicine overall. By continuing to isolate the polygenic nature of man’s temperaments and personality traits, the average person will be better equipped to understand themselves and the people they interact with.


S, Sanchez Roige, et al. "The Genetics of Human Personality." Genes, Brain, and Behavior, vol. 17, no. 3, 2018. ProQuest, http://libraryaccess.sdmiramar.edu:8080/login?url=https://www.proquest.com/scholarly-journals/genetics-human-personality/docview/2019624275/se-2, doi:http://dx.doi.org/10.1111/gbb.12439.

Goleman, Daniel. "MAJOR PERSONALITY STUDY FINDS THAT TRAITS ARE MOSTLY INHERITED." New York Times, Dec 02, 1986. ProQuest, http://libraryaccess.sdmiramar.edu:8080/login?url=https://www.proquest.com/newspapers/major-personality-study-finds-that-traits-are/docview/426370613/se-2?accountid=3881.

Personality Traits: Theory, Testing and Influences : Theory, Testing and Influences, edited by Melissa E. Jordan, Nova Science Publishers, Incorporated, 2010. ProQuest Ebook Central, https://www.proquest.com/legacydocview/EBC/3018065?accountid=38871.

Hamer, Dean H., et al. "Role of the Serotonin Transporter Gene in Temperament and Character." Journal of Personality Disorders, vol. 13, no. 4, 1999, pp. 312-27. ProQuest, http://libraryaccess.sdmiramar.edu:8080/login?url=https://www.proquest.com/scholarly-journals/role-serotonin-transporter-gene-temperament/docview/195234696/se-2?accountid=38871.

van den Berg, Stéphanie,M., et al. "Meta-Analysis of Genome-Wide Association Studies for Extraversion: Findings from the Genetics of Personality Consortium." Behavior Genetics, vol. 46, no. 2, 2016, pp. 170-182. ProQuest, http://libraryaccess.sdmiramar.edu:8080/login?url=https://www.proquest.com/scholarly-journals/meta-analysis-genome-wide-association-studies/docview/1764632276/se-2, doi:http://dx.doi.org/10.1007/s10519-015-9735-5.

Ebstein, R. P. "The Molecular Genetic Architecture of Human Personality: Beyond Self-Report Questionnaires." Molecular Psychiatry, vol. 11, no. 5, 2006, pp. 427-445. ProQuest, http://libraryaccess.sdmiramar.edu:8080/login?url=https://www.proquest.com/scholarly-journals/molecular-genetic-architecture-human-personality/docview/2645758269/se-2?accountid=38871, doi:http://dx.doi.org/10.1038/sj.mp.4001814.

Nature Genetics. (2018, June 28). Heritable Influences on the Mind and Brain. https://www.nature.com/. https://www.nature.com/articles/s41588-018-0172-2

Schoenberg, A. (2021, October 10). Introduction to Physical Anthropology. https://arnieschoenberg.com/anth/bio/intro/section7.html#culture

 Eysenck, H. J., & Eysenck, S. B. G. (1993). Eysenck Personality Questionnaire-Revised [Database record]. APA PsycTests.

Carmichael, Avery. "What the Heck is the Biosocial Theory?". Behavioral Psych Studio, 28 Oct. 2021. behavioralpsychstudio.com/what-the-heck-is-the-biosocial-theory/.

Patnala, Radhika, et al. "Candidate Gene Association Studies: a Comprehensive Guide to Useful in Silico Tools." PubMed Central (PMC), 9 May 2013, www.ncbi.nlm.nih.gov/pmc/articles/PMC3655892/.

"Genome-Wide Association Studies Fact Sheet." Genome.gov, 17 August 2020. www.genome.gov/about-genomics/fact-sheets/Genome-Wide-Association-Studies-Fact-Sheet.

Britannica, The Editors of Encyclopaedia. "self". Encyclopedia Britannica, 10 Apr. 2016, https://www.britannica.com/topic/self. Accessed 5 May 2022.

Grice, James W.. "five-factor model of personality". Encyclopedia Britannica, 4 Jan. 2019, https://www.britannica.com/science/five-factor-model-of-personality. Accessed 4 May 2022.

Jordan, Melissa E. Personality Traits: Theory, Testing and Influences. Nova Science Pub, 2010.

van den Berg, S.M., de Moor, M.H.M., McGue, M. et al. Harmonization of Neuroticism and Extraversion phenotypes across inventories and cohorts in the Genetics of Personality Consortium: an application of Item Response Theory. Behav Genet 44, 295–313 (2014). https://doi.org/10.1007/s10519-014-9654-x

About the Author

Jontel Scott currently attends San Diego Miramar College pursuing an associate's degree in Computer Science. Prior to attending he served in the US Navy for approximately 6 years. That journey has provided him with unique experiences ranging from serving directly under the Secretary of Defense's public affairs department to rendering high quality medical care to foreign nationals in Spain. Currently, he hopes to build his skill set in computer networking, cyber security, and programming to eventually secure a position within the tech industry. Ideally, while taking interesting classes like ANTH 102 he can become a more well rounded student in hopes of  one day attending one of California's coveted UC schools.

“Bipedalism in Australopithecines” by Sergio Armenta

Take a walk. It could be a short walk or a long walk. The muscles around the hip and the bones in the legs carry one’s body step by step or stride by stride. Although it may seem simple it is a defining characteristic of Homo sapiens. It was not always the case that walking on two feet was normal, but a long time ago apes began to climb down from trees and engage in bipedalism. Meaning that they chose to walk on two feet, and over three million years ago the habit of walking on two feet began to take place as seen in Australopithecus. Yet, it was not quite similar to that of Homo sapiens. Anthropologists such as William L. Jungers, Christine Berge, and David A. Raichlen studied the remains of Australopithecus to determine their bipedalism and published their works as articles in journals. An article by Berge titled, “How did the australopithecines walk? A biomechanical study of the hip and thigh of Australopithecus afarensis,” is an extensive study to adequately assess the identity of bipedalism found in Australopithecus. Using this article and others will help to understand the nature of bipedalism found in Australopithecus in East Africa and South Africa, but first an introduction regarding whoAustralopithecusare and the importance of bipedalism.

First things first, let's start with some information regarding the genus Australopithecus. It is now through fossil records that the australopithecines live and through these fossils anthropologists have discovered many intriguing details. For starters there are several species attributed to that genus, such as afarensis, africanus, sediba, and many more. Yet, there was a time when they lived and roamed the Earth. About 4.2 million years ago australopithecines were present and around three million years ago they could be found in East and South Africa (O’Neil 2013). The australopithecines were intermediate between apes and people, as O’Neil continues to add on, and they are the immediate ancestors to modern humans. Because of similarities between australopithecines and modern humans, both can be classified as members of the same biological tribe Homininae (O’Neil 2013).

Since anthropologists have a quest to study humanity, more specifically its evolution, behaviors, and culture-australopithecines may provide some insight. In the history of human evolution there are three significant trends that lead to modern humans: bipedalism, stone tools, and encephalization (bigger brain). It is bipedalism that is most attached to the australopithecines as they were among the first to take steps with only two feet instead continuing to walk on all fours (quadrupedalism) such as chimpanzees and other primates. The significance of bipedalism is best put, “Footprints have become an icon of humanity, some left by an australopithecine around 3,500,000 years ago, which led to footprints on the moon” (Schoenberg 2022, 6.1). To emphasize the importance of bipedalism:

Using two feet instead of four is more efficient for traveling long distances. Walking on two feet freed our hands for tools and communication. Walking tall meant we could see over the tall grass of the savanna to notice food and predators, and it could have help intimidate rivals or predators, and some claim that it would have helped us wade through shallow water. Getting up off the ground could have kept us cooler in hot savanna heat, by moving our head farther away from the hot ground, and decreasing the amount of sun our bodies got when it was at its strongest. [Schoenberg 2022, 6.1]

It is a generally accepted fact that australopithecines are bipedal, but it is the level of bipedalism that they acquired which is a mystery. Specifically, did they walk with extended hips and knees (EHEK) as modern humans did or did they walk with a bent hip and bent knee (BHBK) as chimpanzees and other primates; and the role it played that led to modern humans also has puzzled anthropologists. Again, since anthropologists (biological anthropologists to be more precise) are searching for clues that pertains to the evolution of humans, they look no further than to the remains of australopithecines.

Evidence of bipedalism can be found using the bones of extinct australopithecines. In 1974 a team of paleoanthropologists, led by Donald Johanson, found partial skeletal remains (40 percent complete) at Hadar in the Afar desert region in Northern Ethiopia (O’Neil 2013). The species specifications are an adult female at 3 feet 3 inches (1 m) with a weight of 60 lbs (27 kgs) and they classified her as Australopithecus afarensis (O’Neil 2013). The team also gave her a name, Lucy; and she lived around 3.2 - 3.18 million years ago. With this discovery many anthropologists began to study her to find answers to the many questions they had. Eight years after the discovery, Jungers assessed the bones to determine the locomotion of Lucy. Comparing the forelimb (humerus bone) and hindlimb (femur bone) of Lucy to modern humans, Jungers results indicate “that forelimb of A. afarensis (as represented by Al 288-1[Lucy]) were already comparable with those of modern humans, but that the hindlimb of this early hominid was relatively short and proportionally similar to that of a small pongid [great apes]” (Jungers 1982, 677). This showcases that modern humans and australopithecines, such as Lucy, are still anatomically different and it will illuminate the differences in bipedalism. In addition to those results, Jungers concludes that there is other compelling evidence of bipedalism such as the pelvis and knee, yet “the relatively short hindlimb of Lucy implies substantial kinematic differences of bipedal gait from modern conditions. Both relative and absolute stride length were necessarily reduced in AL 288-1” (Jungers 1982, 677). In other words, Australopithecus afarensis can walk bipedally, but it is not equivalent to that of modern humans because the short hindlimb is a limitation. So there is a new piece to the puzzle that anthropologists are trying to solve and it showcases that the australopithecines have not reached the level of bipedalism that modern humans use.

Furthermore, in another article by Jungers he reaches the same conclusions. “To reiterate, Lucy's femur is not of the length that would be expected in modern humans of her size” (Jungers 1983, 676). This adds more support to the previous article, which first stated this conclusion, but unlike the other article this one goes into greater detail about the implications of the limb proportions in Lucy.

Comparisons of body proportions and gait in chimpanzees to A. afarensis have been shown to be very relevant. Reynolds (1983) notes that the stride length of the Laetoli hominids are the same as those predicted for a chimpanzee of Lucy's size walking bipedally. Our own observations on bipedal walking by two chimpanzees with hindlimb lengths of approximately 0"5 m (about the same as Lucy) have revealed that the ranges of stride lengths they use overlap those of both trails at site G. Therefore, even if Lucy's bipedal gait were chimp-like, she still could have made either of the trails at site G. [Jungers 1982, 681-682]

The main takeaway from this is that Lucy’s bipedalism can be compared to a chimpanzee and it is not quite identical to modern humans. Something that Jungers reiterates again in this article is that hindlimb may have elongated due to evolution (Jungers 1983, 681). Given that Lucy’s hindlimb is shorter than modern humans it can be inferred that a longer femur will enable one to become habitually bipedal.

Similarly to Jungers, another anthropologist evaluates the remains of Lucy to determine how australopithecines walk. This time around the constraints on the hip and the actions of the gluteal muscles around the hip and thigh will help determine the bipedality of Australopithecus afarensis (Berge 1994, 260). The results for finding the constraints are straightforward, “the pelvic and femoral morphology in Australopithecus appears to be disadvantageous for weight bearing and introduces increased bending” (Berge 1994, 263). There seems to be more limitations to Lucy other than the short hindlimb that prevents her from comparable walking to modern humans. Furthermore, to help understand why the hip of Lucy may be inefficient is because of the anatomical differences once again. The hips of modern humans are short and bowl-shaped and the australopiths did not have a hip similar to that until three millions years ago, which is well after the lifetime of Lucy (O’Neil 2013). Moving along to the second part of the experiment, Berge creates two hypothetical reconstructions of the hip. The first being a human-like gluteal pattern reconstruction and the second being an ape-like gluteal pattern reconstruction. There had to be two reconstructions because the fossil remains are not clear enough to indicate what the muscle pattern of Lucy was (Berge 1994, 264). That being said, movements in the frontal plane, sagittal plane, and transverse plane all suggest that the ape-like reconstruction provides more ability than a human-like reconstruction (Berge 1994, 267-270). To conclude, Berge gives her analysis:

The present results lead to the conclusion that the bipedalism of Australopithecus must have differed from that of Homo. Not only did Australopithecus have less ability to maintain hip and knee extension during the walk, but also probably moved the hip and lower limb differently. It seems that the australopithecine walk differed significantly from that of humans, involving a sort of waddle gait, with large rotatory movements in the pelvis and shoulders around the vertebral column. [Berge 199, 271]

So, it is fair to say that Lucy and perhapsAustralopithecus afarensis of her time did not quite match the bipedalism as seen from Homo sapiens. Yet, it is now clear that they did engage in bipedalism and will continue to do so to create the trend that will lead to modern humans.

So far Lucy’s remains highlight that she and other australopiths are in-between apes and humans. They demonstrate the metaphor of mosaic evolution. Meaning that “a living species can be seen as the evolution of many characteristics” (Schoenberg 2022). In addition, anthropologists have a better understanding of bipedalism in human’s evolutionary history, which can be quite difficult with the limited evidence.

Correspondingly, fossilized footprints may provide another avenue to understanding the bipedality of australopithecines. Continuing to stay in East Africa, but moving on to Laetoli, five consecutive bipedal footprints were discovered in 1976 and they were dated back to 3.6 million years ago (McNutt 2021, 468). The only problem with these footprints is that initially they were considered to be from ursids (bears); and upon further study McNutt and his team determined that the footprints are hominin, but not Australopithecus afarensis (McNutt 2021, 469). They did not attribute the footprints to A. afarensis because the third fossilized step indicated a diverging hallux. For those that do not know, a diverging hallux means that the big toe is not aligned with the other toes because it goes in an opposite direction similar to chimpanzees. This led to the conclusion that a bipedal hominin left the footprints at Site A with a more primitive foot than A. afarensis (McNutt 2021, 471). The big takeaway from this is that it was a bipedal hominin, which lived much earlier than Lucy, and since this is farther back in time the anatomy of this australopith may have retained some ape-like characteristics. Not being able to identify the species that left the footprints behind is not helpful, but it helps to understand that the trend of bipedalism had a much earlier start. The path to modern humans still has many steps to go.

Equally important, Site G at Laetoli contains footprints as well. This time around estimated velocities of early hominins may provide answers for their locomotion. (Raichlen 2007, 113) To find the estimated velocities four cases are created: human hip-height with human stride-length, human hip-height with chimpanzee stride-length, chimpanzee hip-height with chimpanzee stride-length, and chimpanzee hip-height with human stride-length. (Raichlen 2007, 114) The results suggest that the footprints left at Laetoli Site G, could have been made by an early hominin using either human-like locomotion or chimpanzee-like locomotion models. (Raichlen 2007, 115) This is really interesting because the previous articles suggest that the australopithecines used a different bipedalism compared to modern humans, but this study suggests that australopithecines can use a human-like bipedalism. Meaning that australopiths could have used an extended hip and knee such as modern humans. The results may seem contradictory to the other articles as well, but they do provide more support for australopiths bipedality because if australopiths chose chimpanzee-like locomotion then it is different from modern human locomotion. Also the other studies suggest that the kinematics is what separated the australopithecines from modern humans in regards bipedalism. It also gives more credence to the mosaic evolution metaphor because it is a mixture of both chimpanzee-like characteristics and human-like characteristics. Only with the introduction of more evidence will this puzzle be solved.

Furthermore, Raichlen continues to study more footprints in Laetoli Site S. Differently from the previous article, they “test the hypothesis that the new Site S prints show similar morphology compared with the Site G prints and are also consistent with extended limb bipedalism,” and the results leads to the conclusion “that the footprints of the two newly discovered individuals walking at Laetoli are consistent with bipedal mechanics that included a generally extended hip and knee, although their kinematics may not necessarily be identical to the modern human pattern” (Raichlen 2017, 135). Again, the kinematics is differentiating australopithecines and modern humans. However, it is important to note that the posture of australopithecines (EHEK) may be shifting towards modern humans, but the velocity is still no match for modern humans.

So, footprints in Laetoli provided some answers to the level of bipedality of Australopithecus afarensis, but there are more species under that genus. Moving on from East Africa to South Africa, where Australopithcus robustus andAustralopithecusafricanus dwell. It should be mentioned that A. robustus has its genus reclassified a number of times, but for the sake of this they are under Australopithecus.It should also be mentioned that A. africanus coexisted with A. afarensis (3.7-3.0 million years ago), but went on to exist for 500,000 thousand years after A. afarensis.Australopithecus robustus lived from 2.0 million years ago to 1.5 million years ago (O’Neil 2013).

With that information out of the way, fossilized bones are once again important to discovering the bipedalism of Australopithecus. The first metatarsal of a 1.5 - 1.8 million year old hominin was discovered and it provided clues that helped determine if A. robustus had similar posture while walking and toe-off as modern humans (Susman 1988, 7). The results revealed that “it would appear that the foot of Paranthropus [A. robustus],...,was devoted to plantigrade bipedality. Indications are, however, that the South African robustus had not achieved fine-tuning of the toe off mechanism seen in later hominins”(Susman 1988, 14). The results are interesting because it seems that A. robustus managed to acquire a bipedality closer to modern humans, but similar to their predecessors it lacked a characteristic. So after one and a half million years from the footprints in Laetoli and Lucy, progress was made. However, not to take away from their progress the metatarsal still resembled a mosaic pattern of primitive and derived features (Susman 1988, 11). This is a trend that exists within australopithecines and perhaps a reason as to why they are considered a transitional species.

Similarly, the tibia and ankle would be used to test if A. africanus walked with EHEK or BHBK by comparing it with modern humans; and the results do indicate that, “The most likely interpretation of these data is that the Sterkfontein hominins loaded their distal tibiae using human-like ankle angles, hence a relatively extended lower limb posture” (Barak 2013, 3, 4-5). It is unclear when this hominin lived, but the more fascinating part is that the trend of bipedalism is heading towards modern humans. It seems that the closer time gets to Homo sapiens, walking on two feet is becoming more proficient. To conclude Barack states, “in light of such adaptations, it is unsurprising that efficient, humanlike walking evolved inAustralopithecusprior to the genus Homo” (Barack 2013, 6) It is a well known fact that Homo erectus are stone users, but an even more important fact is that walking on two feet has earlier origins. It is the australopithecines that enable modern human’s bipedalism.

All in all, bipedalism in Australopithecus has a long history. From footprints to bones and across species, the nature of bipedalism seen from Australopithecus has been contested. Initially it was not equivalent to that of modern humans and as time went on australopiths began to master it a bit more. As mentioned earlier, bipedalism is a trend that led to modern humans. Although all three trends are equally important, bipedalism had earlier roots as it predates stone tools and encephalization. The relevance of bipedalism in Homo ancestors may be brought into question, but it must be remembered that biological anthropologists are in the field of studying human evolution. Notice how most of these studies compared australopithecines to modern humans. While it is important to learn about and understand bipedalism in Australopithecus it more so reflects back on to modern humans. When having taxonomic discussions and using the tree of life analogy, it is crucial where Homo sapiens are placed. Biological anthropologists are keen to discover and understand Homo sapiens origins. Starting over three million years ago, early hominins such as australopithecines walked on two feet and set a path that Homo sapiens continue to walk on. That path being bipedalism and evolution.


Barak, Meir M., Daniel E. Lieberman, David Raichlen, Herman Pontzer, Anna G. Warrener, and Jean-Jacques Hublin. “Trabecular Evidence for a Human-like Gait in Australopithecus africanus.PLoS ONE 8, no. 11 (November 5, 2013). https://doi.org/10.1371/journal.pone.0077687.

Berge, Christine. “How Did the Australopithecines Walk? A Biomechanical Study of the Hip and Thigh of Australopithecus afarensis.” Journal of Human Evolution 26, no. 4 (1994): 259–73. https://doi.org/10.1006/jhev.1994.1016.

Jungers, William L. “Lucy's Limbs: Skeletal Allometry and Locomotion in Australopithecus afarensis.” Nature 297, no. 5868 (June 24, 1982): 676–78. https://doi.org/10.1038/297676a0.

Jungers, William L., and Jack T. Stern. “Body Proportions, Skeletal Allometry and Locomotion in the Hadar Hominids: A Reply to Wolpoff.” Journal of Human Evolution 12, no. 7 (1983): 673–84. https://doi.org/10.1016/s0047-2484(83)80007-4.

McNutt, Ellison J., Kevin G. Hatala, Catherine Miller, James Adams, Jesse Casana, Andrew S. Deane, Nathaniel J. Dominy, et al. “Footprint Evidence of Early Hominin Locomotor Diversity at Laetoli, Tanzania.” Nature 600, no. 7889 (2021): 468–71. https://doi.org/10.1038/s41586-021-04187-7.

O'Neil, Dennis 2012 "Primate Behavior" Biological Anthropology Tutorials https://www2.palomar.edu/anthro/behavior/default.htm August 22, 2016

Raichlen, David A., Herman Pontzer, and Michael D. Sockol. “The Laetoli Footprints and Early Hominin Locomotor Kinematics.” Journal of Human Evolution 54, no. 1 (2008): 112–17. https://doi.org/10.1016/j.jhevol.2007.07.005.

Raichlen, David A, and Adam D Gordon. “Interpretation of Footprints from Site S Confirms Human-like Bipedal Biomechanics in Laetoli Hominins.” Journal of Human Evolution 107, (2017): 134-138. http://dx.doi.org/10.1016/j.jhevol.2017.04.002

Schoenberg, A. (2022). Introduction to Physical Anthropology. Arnie Schoenberg. Retrieved February 2022, from https://arnieschoenberg.com/anth/bio/intro/index.html.

Susman, Randall L., and Timothy M. Brain. “New First Metatarsal (SKX 5017) from Swartkrans and the Gait Ofparanthropus Robustus.” American Journal of Physical Anthropology 77, no. 1 (1988): 7–15. https://doi.org/10.1002/ajpa.1330770103.

About the Author

Sergio Armenta is a student at San Diego City College. One of his academic goals is to graduate from a four-year university with bachelors in computer science. In the fall of 2022 he will transfer to University of California Santa Cruz and he looks forward to any opportunity to continue his academic career. Provided that Sergio graduates from a university, he will pursue a career as a machine learning engineer. He plans on becoming involved in the process of developing artificial intelligence.

“Habits of a Chimpanzee” by Laura Young

We go to zoos for entertainment and to engage with all the animals there. We want to see them eat, interact with other animals and the zoo keepers, go to a Q&A or informative shows. We go to watch all of these animals in these zoo habitats, which for us humans are normal because this is the only place we can observe these animals unless we were to go out into the rainforests, plains, deserts, oceans, etc. But for these zoo animals, the zoo is not their biological home, and is actually quite foreign for them. It begs the question- which behaviors are normal and which behaviors are abnormal to an animal in captivity? I will be conducting a primate observation at the Sacramento Zoo on the chimpanzee, one of the human’s closest biological relatives next to the bonobo.

First, we must understand the importance of conducting these observations and what relevance it has in the study of anthropology. The short definition of anthropology is the study of humans. But in order to understand human behavior we also must look at the behaviors of our closest relatives, primates. Fuentes, a U.S. biological anthropologist, gave the great explanation of the origins of the word anthropology, but he also expands on his definition, “anthropology is the study of humans (us) and our closest biological relatives other members of the order Primates—monkeys, apes and prosimians” (Fuentes 2012, 15). Anthropology is broken down into 4 subcategories- biological, cultural, linguistic, and archaeological. Primatology studies the behavior of primates and usually falls under the sub categories of biological, cultural, and linguistic. Additionally, primatology is based around comparing and contrasting primates to other mammals, and then to ourselves (Schoenberg).

During my observation of the chimpanzee at the Sacramento Zoo I believe I will find some abnormal behavior. I will be recording behavior based on behaviors recorded from a previous study conducted in zoo captive chimpanzees. This study is called, “How Abnormal Is the Behaviour of Captive, Zoo-Living Chimpanzees?”, and it was conducted by Lucy P. Birkett and Nicholas E. Newton-Fisher. They found the following behaviors atypical of chimpanzees living in their natural habitat. I will not in any way provoke the chimpanzees by trying to interact, tap on glass, make any aggressive or sudden movements, or anything else that may cause a reaction from the primates. I do believe that this could be a difficult study because of my limited time I have available during my observation. But I hope that by taking a scan every 10 seconds and recording any behavior that I find, I will observe some of these abnormal behaviors. I believe my results will be similar to those of Lucy P. Birkett and Nicholas E. Newton-Fisher, but with significantly less data.

Abnormal Behavior & Definition

Bang self against surface- hit own body-part against solid surface.
Bite self- bite own body-part.
Bite-hit-lick self - bite, hit, and lick own body-parts in constellation.
Bounce - bounce body or head, in non-social context.
Clap - slap palm of hand or sole of foot, making noise.
Clasp self - clutch own body.
Configure lips - move lips stereotypically, such as repetitively blowing air through lips or wiping lips over glass.
Display to human - stylized agonistic display and build-up directed at humans.
Drink urine - drink own urine.
Eat faeces - ingest own faeces, both matrix and undigested items (coprophagy).
Eat faeces of other - ingest another’s faeces, both matrix and undigested items.
Float limb - entire limb (not just fingers or toes) appears to move independently, as if it does not belong to individual.
Fumble nipple - manipulate own nipple(s) with thumb or fingers. May suck on nipple if breast or nipple is extended.
Groom stereotypically - repetitively groom self on specific body part, seemingly without goal.
Groom stereotypically with object - groom self seemingly without intention, with stick or other tool. Drag object lightly over hairless body surface in non-focused way.
Hit self - hit own body-part with hand.
Incest - copulate with immediate relative.
Jerk - spontaneously jerk body, apparently unprovoked by external stimulus.
Manipulate faeces - hold, carry, or spread own or other’s faeces on surface.
Move hand repetitively - repetitively move hand in circular fashion in air or through substrate.
Pace - locomote, usually quadrupedally, on substrate, covering and then re-covering route in stylized fashion, with no clear objective.
Pat genitals - repetitively touch own genitals, then often lick hand.
Pinch self - compress own skin between thumb and forefinger.
Pluck hair - pull out own hair.
Pluck hair of other - pull out another’s hair.
Poke anus - insert finger into own anus.
Poke eye - poke one or more fingers into own eye.
Regurgitate - vomit voluntarily, then usually re-ingest vomitus.
Rock - sway repetitively and rhythmically, without piloerection. Usually side-to-side movement, but may be forward and backward or full circular motion of torso. Usually whole body, sometimes just the head.
Rub hands - run one hand over the other, then repeat but reverse the hand order, in stylized fashion.
Spit - expel saliva through pursed lips, often directed at human observer.
Stimulate self stylized, no context - repetitively stroke or fondle own penis or clitoris in non-mating context.
Toss head - circular movement of head.
Touch urine stream - place hand or foot in own urine stream. May wipe hand on body after.
Twirl - rotate torso on axis for 360 degrees while upright and bipedal.
Twitch body-part - body-part, often fingers and toes, twitch repetitively, apparently involuntary.
Walk on object - locomote bipedally while carrying object (e.g. blanket), stepping on object edges that drag on floor.

[Birkett LP, Newton-Fisher NE 2011]

On May 1st, 2022 at 1:15pm I went to the Sacramento Zoo to conduct my chimpanzee observation. There I observed four chimpanzees from behind thick glass. The four chimpanzees included Doug, who is the male leader of the group, Amelia who is mother to Maria, and Pablo. When I first started my observation, all four were found in the left corner of the enclosure, near the cave feature. They were grooming each other at this point, which is not an abnormal behavior of a chimpanzee. Although, perhaps what could make this behavior abnormal is grooming without a goal, or stereotypically. I am unsure if they were grooming each other in a stereotypical manner because it seemed they did have a goal in mind - to clean the other. They used their hands and mouth to achieve this goal.

From the back left corner, one decided that it was time to change areas, and the rest followed. I could not tell who was the initiator at this moment. Additionally, I did not hear any vocal communication/ques to start the migration. The leader went up the climbing feature to the top, then the 2nd, 3rd, and 4th followed. All four found a resting place at the top of this feature. They all sat on top perched by themselves in different areas of the feature, but all facing the same direction.

After some time, things became interesting. One made a loud vocal call, but I could not hear who it came from. Then, Maria (daughter) embraced Amelia (mother). She burrowed in her mother’s chest and (although I’m not entirely sure because it was difficult to see) it looked like she was suckling on her mother’s nipple.

After about a minute embrace they decided it was time to come down from the climbing feature. One by one they came back down to the floor of the enclosure. They decided to go back into the cave feature that was away and out of sight. But it wasn’t long until they decided to come back out!

They re-emerged from the cave and were very active at this point. They seemed to be communicating to one another, and one actually bit the other. Then, I saw the zoo employee, and realized it was feeding time. They are fed at the top of the enclosure, so they must climb and hang onto a gated area at the top. They each proceeded to climb. Pablo (I believe) started rocking back and forth before getting fed. This was the first abnormal behavior I observed. Once they started to receive the variety of fruits and vegetables, I saw Maria reaching for her mother’s food. The mother then took her food and was the first to climb down, so she could eat in peace.

Pablo turned around so he was facing the observers to eat. Amelia started foraging for food that had been dropped. Maria climbed down and the two females stayed close to each other, then eventually separated, one going inside the cave and the other going to the far-right end of the enclosure. Pablo eventually came down and sat next to the female at the far-left end. She shared a piece of zucchini she was eating by throwing it on the ground for him to pick up.

Although at some moments members of the group would come together, it was the first time I observed them separating from each other and doing their own thing individually.

Pablo came over after he finished his portion of the shared food and ate straw in front of the window. He also took this time to stare at one of the human observers. Another chimpanzee came to the front of the enclosure and moved a bag, which I noted as the second abnormal behavior. After about a minute, the males and females formed grooming pairs. They again used their hands and mouth to groom each other.

Once grooming finished up, the leader decided it was time to climb again. But this time the leader climbed with a bamboo stick in his hand. So, the others followed. But each made sure to grab a piece of bamboo before making their way up the climbing feature. I found this fascinating as I watched each chimpanzee grab their stick of choice. Almost as if it was a requirement to grab the stick, as the leader did, in order to start their climb. Once they found their comfortable spot of choice on the feature, they each ate their bamboo, then dropped the excess on the ground.

What I noticed is how observant they are of each other. There was not always a vocal que, although once there was, but there was always a gesture or movement that each would follow. I did not gather a ton of data that pointed to abnormal behavior. I did observe two moments of stereotypical grooming (although it was hard for me to tell if this was stereotypical or not), one moment of swaying, one moment of pacing, and one moment of movement bipedally with an object (bag). Although I did find some slight evidence of abnormal behavior, I do not feel like it is strong enough to suggest true abnormal behavior, especially since I am not certain if what I saw was truly abnormal or normal due to my lack of experience. So, I would say this observation disproved my hypothesis that I would find similar data to the previous observation conducted by Birkett and Newton-Fisher.

I think the most interesting observation was the mirroring of the leader. Each would do exactly as the leader, down to picking up a stick in order to climb the feature, just as the leader did. I was in awe of how observant and aware they are of each other.

Additionally, I observed that the orangutans had three members in their enclosure. Although in the wild they would typically live alone until it was time to find a mate. In the wild they would call and eventually this call may or may not be answered. But here they lived together. I found this fascinating and am still unsure if this would be abnormal, or important that they live in the company of one another since they do live in captivity.

After my primate observation at the Sacramento Zoo, I did not observe any significant abnormal behavior from the family of chimpanzees, which rejects my hypothesis. I did however observe very interesting behavior that suggested they mirror and follow each other’s movements. I also noticed how observant and aware they are of each other. Additionally, I did find it interesting that another primate at the zoo, the orangutan, lives with each other in a community, as opposed to their usual independent lifestyle they would live in the wild.


Fuentes, Augustín. 2012 Biological Anthropology: Concepts and Connections. 2nd ed. Boston: McGraw Hill.

Birkett LP, Newton-Fisher NE (2011) "How Abnormal Is the Behaviour of Captive, Zoo-Living Chimpanzees?" PLoS ONE 6(6): e20101. doi:10.1371/journal.pone.0020101

About the Author

Hello everyone! My name is Laura Young (she/her), and I am very excited to be studying anthropology with you all! With the completion of Anthropology 102 and 104 I will have completed my AS in business administration, and I plan on transferring to Sacramento State this fall 2022 to further study finance. I believe this course will help advance my writing, research, and remote group collaboration skills, which will be a huge advantage for my career.

I currently work as an Executive Assistant for a risk analytics consulting company. My job requires a good amount of technical writing, so I have quickly begun to understand the importance of good communication and writing skills. My goal is to continue building my career within the operations department, and to build my consulting skills.

I believe the study of humans and their behaviors will be a very enjoyable topic, so I look forward to the curriculum. Sometimes writing for me is daunting and anxiety inducing. But, studying something that I enjoy can help ease the process. And working in a synergetic, team environment will be not only helpful, but also fun!