Classifying Human Biodiversity at the Population Level Sergio Guerra

Taxonomically speaking, the most specific classification group which humans fall under is Homo sapiens. Historically, the classification system created by Carolus Linnaeus has provided and created major problems in society, not just in America but throughout the world. The species classification was used to divide humans up into races, suggesting that humans were different from each other based not only on phenotypic and outward characteristics, but also genetically, intelligently, mentally, psychologically, and so forth. The racial studies that spawned from such groups triggered the creation of a rash of racist ideologies, eventually segregating and marginalizing African-Americans, the Japanese, Irish, and millions of other immigrants looking to call the “Land of the Free” home. However, with the emergence of new schools of thought, biogenetic discoveries, and human rights efforts, scientists are now recognizing the effects of species level classifications and making the shift to groupings on the population level.

Over the course of history, scientists such as Blumenbach, Morton, and many others used “science” to justify the formation of races, which ultimately led to divisions in society, often placing African-Americans and minorities in general at the bottom rung of the social hierarchy. Blumenbach proposed various racial classifications, often describing non-white populations. He would place non-whites into various racial groups, in essence claiming they were intrinsically different from one another, while placing Europeans into only a few (Marks 2008). Morton used craniometry in an attempt to demonstrate different racial categories under which he claimed all people could be divided and placed. His work led to the concept of polygenism which put forth the idea of separate origins of the different “species” aka “races” of humans (Marks 2008). The groups were titled “Caucasian,” “Negro,” and so forth. When people began to realize that science was supporting the idea of human difference and the existence of races, they also began to believe that humans had originated from different “Adams” as well. This thinking was then used to justify colonial conquests, exploits, and atrocities committed during expansion.

The concept of biological lineage coalescence slowly began to change such viewpoints, and tackle the issue of polygenism. Basically this school of thought says that if you trace back far enough into history, the human lineages begin to coalesce and come together. If it can be traced back far enough, human lineages will eventually be able to come back to a shared point, basically indicative of a single common ancestor. The concept aligns itself with the monogenesis theory regarding the origin of humans. In essence it claims that all humans originated from the same place and thus, a common ancestor. The prevailing scientific viewpoint suggests Africa to be the center of human origin. The concept itself is very important because it combats the claims made by those believing in polygenesis. When polygenesis first began taking hold in the 1700s and 1800s, racial theories were claiming that humans could be divided into races, that intellectual capabilities were not evenly distributed among the races, and that mental capabilities were associated with certain racial features (Mielke et. al 2006). Accompanying these studies were historical events such as the conquest of Native American lands, manifest destiny, slavery, and other colonial exploits and endeavors. As colonists were moving westward and wiping out tribes, while enslaving Africans, they were maintaining the idea that the people of these different “races” were of another species. Since “science” had “proven” the existence of differences between these groups, colonists believed them to be accurate and used the data to justify their wrongdoings. By claiming that the concept of polygenesis was the true explanation of human origins, colonists were able to justify their actions and quash their moral qualms about the massacres and atrocities being committed. By validating the concept of biological lineage coalescence and monogenism, the theory proposing human origins from different “Adams” slowly toppled (Mielke et. al 2006). The human biological lineage coalescence concept directly counters the polygenistic standpoint and foundational points. If it is possible to trace the human lineage back into the far reaches of history, generation after generation and ancestor after ancestor, and demonstrate the merging of human lineages regardless of “race” or ethnicity, then all of the principles of polygenism are no longer valid and have no scientific merit whatsoever. Human biological lineage coalescence can be used to dispel many of the stereotypes and racist ways of thinking, which have been used in the past to separate human groups. By demonstrating the shared ancestry of all humans, society began to slowly learn to embrace all people, regardless of simple phenotypic differences.

Many of the species level investigations conducted in the past were more or less artfully disguising the reality of what they were truly studying. Behind all of the scientific jargon, the investigations were nothing more than racial studies. Racial studies are examinations of the biological differences among groups (Marks 1995). When the results are skewed and applied in a socio-cultural context to justify superiority or racism, as is often done, problems arise. It was often the case that the scientists seeking to investigate differences between human groups were often the ones who would find such differences significant and use them to assert power and justify pre-existing social conditions. If all social groups received equal treatment, equal rights, equal opportunity, etc. and the application of results was monitored, then racial studies would be fairly straightforward. However, value judgments are often placed on findings and then designations of human “races” begin to affect people’s welfare. A person of mixed ancestry can be assigned to a particular racial group, while genetically they can be anything in between. Therefore the heredity of race is social, not genetic, and based on non-scientific, folk concepts of heredity. As the miscegenation laws in America prohibiting marriage between blacks and whites stated, one needed to have only one great grandparent be black to be considered as black. Blood was seen to be “polluted” when mixed with ethnic ancestry. As seen, often the generalizations created are unfavorable and attributed to a group with little say in order to separate and highlight supposedly “better” traits in more powerful groups. Scientists must be willing to accept responsibility for one’s own scientific conclusions, as they often create racial prejudices and group-wide generalizations that simply aren’t true. When Carleton Coon mistakenly attempted to infer race from fossils, using the premise that there are large groups of humans that differ fundamentally from others, Dobzhansky realized what was fundamentally wrong about Coon’s “scientific” conclusion. Dobzhansky understood the paradox saying, “It is the duty of a scientist to prevent misuse and prostitution of his findings (Marks 1995).” Unfortunately, for hundreds of years such viewpoints were ignored.

In today’s world, after the civil rights movement and the recognition by anthropologists of their contributions toward the genocide brought about by Nazi Germany, the preferred area of study regarding human biodiversity is at the population level. Race is very much a social construct, and when humans are being distinguished from one another like animals are by looking at the species level, problems arise. Humans, unlike other animals, must deal with societal values, perceptions, and problems. For example: If fruit flies are grouped along the species level, no effect is felt by the fruit flies. Flies are not affected by the social values and implications of such groupings. They do not have culture and a mechanism of attaching meaning to “racial” level classifications. However, if humans are grouped in such ways, racist tendencies begin to emerge as they have in the past, with one group attempting to assert dominance, power, and authority over others, in fear that they may lose potential privileges and prerogatives they wish to have and keep. Humans are constantly attempting to secure more and more for themselves and their kin, often using typological classifications to ascertain a spot at the “top.” Those drives for power eventually turned race into a category in which individuals would be placed, regardless of biological history. In turn, this made race an abstraction, with identifiable characteristics varying in people, and perfectly applicable to only a few, making it rather dubious. When social stigmas were added atop such abstractions, divisions quickly emerged.

Although massive strides have been made in regards to scientists realizing the affects of their actions, concern over race still looms heavily today. In a study conducted by the Federal Center for Disease Control looking at classification data from the National Center for Health Statistics before 1989, severe missteps were found which were directly caused by racial classifications (Marks 1995). It was found that at birth, when certificates were being completed describing the newborn, they were placed into racial categories based mostly on subjective reasoning. If one parent was non-white, the child was placed into the non-white parent’s racial group, and if both parents were non-white, then the race corresponded to the father’s group. Eventually, about 5% of babies labeled as non-white at birth were labeled as white at death, severely under-reporting infant mortality rates in non-whites (Marks 1995). Such statistics often leave many of the necessary groups empty-handed and unable to receive the appropriate medical care because it is incorrectly being afforded to another group. Even more obvious racial level biodiversity categories can also be seen in US census data, distinguishing Asians, Eskimos, Aleuts, and people of Hispanic ancestry, but not breaking apart the “White” category, not unlike the early classification systems proposed by Blumenbach and so forth (Marks 1995). Clearly, more steps still need to be taken in order to educate the masses about the “racial” remnants still very much present in today’s society.

In the end, there are a few main points which can responsibly summarize human classification. Firstly, analysis of diversity in humans should remain at the population level. Science must be grounded in realities, not abstractions and findings should never be used to justify superiority, perfect races, hierarchies of humans, or any racist ideas. Secondly, since race is largely a socio-cultural construct, and because humans have always migrated and interbred, classifying humans beyond the population-level is a fleeting idea. Diversity should be analyzed by examining diversity existing within populations, among populations, and among groups of populations. Lastly, human behavior is extremely plastic. Many customs, behaviors, etc. are mixed between groups and shared. The practices, rituals, or any other cultural markers attached to groups cannot be used to justify racist classifications, as they are often shared between many who are well outside of the specific ethnic classes to which they are said to come from. However, when all is said and done, these ideas will never take hold unless people truly grasp the justice it affords to all. If people do not inherently understand such concepts, a long dark road awaits humanity until it becomes ingrained in us all.

With the biogenetic discovery and understanding of the fact that more diversity exists within populations than between them, it seems clear that the best place to keep studies of human biodiversity is at the population level. In today’s day in age anthropologists tend to steer away from classifying humans based on the species level and instead look to the population level for any diversity between humans. Not all anthropologists do so, but the majority recognize the social implications of looking for diversity at the species level. If this society is ever going to be truly equal, classifications propagating such viewpoints must be eliminated. If we are constantly faced with questionnaires and boxes to check, splitting the human population into seemingly separate, different, and distinct categories, how will anything ever change? When the data, the facts, and real scientific information is put into practice and society begins to actually “walk the walk” instead of simply talking about change, will the separatist culture finally begin to bring people together, rather then attempting to explain why we are so far apart. When and if these changes will happen, only time will tell.

There is always a reason for one trait being present over another. Through either sexual selection or natural selection, often a combination of the two, specific traits are chosen for survival purposes or because those traits were seen as attractive in that society. There are many traits that are attractive to different societies that do not have much, if anything to do with survival. Some examples are height, eye color, or hair color. Other traits are selected for through natural selection, such as resistance to disease, to help the individual survive and pass along the good genes. Most traits though, are a combination of both; traits can be seen as attractive because they show good health, such as a healthy weight.

Many of the culturally selected traits are phenotypic, such as height or hair color. One trait was culturally selected for in China was small feet on women. Since small feet were seen as beautiful, the males would only want to mate with females who had small feet. In the beginning, this would have eliminated the gene that made women’s feet larger than a certain size. Instead, smaller and smaller feet became attractive, so Chinese women were forced to bind their feet to be seen as beautiful. After women started binding their feet, the gene coding for small feet was no longer being chosen for, because the women were altering their appearance, much like someone getting plastic surgery or wearing colored contact lenses would be today. The gene coding for whatever was being “fixed” does not change, just the phenotype. That person’s children would not be born with the trait looking the way it would after it was fixed, but before the trait was fixed.

Another selected trait in some cultures is large hips on females. These probably began because people realized that women with large hips seemed to have had an easier time giving birth and were less likely to have major complications while giving birth. This trait can actually be both sexually selected for and due to natural selection. If a woman with small hips became pregnant and died in childbirth because the baby’s head was too big or the woman’s pelvic bone was too small, her genes would only be passed on to that one child, if it survived. Another woman with larger hips could have more children and pass her genes on to more people. Since hip size is obvious, males can choose to reproduce only with women with large hips, therefore sexually selecting for it.

There are some culturally selected traits that can not be known just by looking at a person. An example of this is lactose tolerance and intolerance. The “normal” trait is lactose intolerance. Lactose is very important during infancy in mammals. Infants receive all nutrients of their through their mothers milk. The enzyme, lactase, which is responsible for digesting lactose, is located in the small intestine. Lactase is produced from the beginning of the second trimester and continues at high levels until just after weaning age, between two and five years in most societies. After weaning, lactase production drops to between 5% and 20%. Lactase persistence or restriction is determined by the LCT locus. There are three LCT alleles, LCT*P, LCT*R, and LCT*C. LCT*C is very rare in comparison to LCT*P and LCT*R. Those with the genotypes LCT*P/LCT*P and LCT*P/LCT*R are both lactose tolerant, whereas those with the genotype LCT*R/LCT*R are lactose intolerant (Mielke 2006). But what explains the distribution of lactose tolerance and intolerance?

Lactose tolerance can be considered both a sexually selected trait and due to natural selection. Since mammals generally stop being able to digest lactose after the weaning stage, there must have been some selective advantage to being lactose tolerant into adulthood. In areas where there is a high instance of milk consumption, there is also a higher percentage of lactose tolerance, such as areas like northern Europe and parts of Africa and Asia. According to the researcher, Tuula H. Vesa, there is a lactose intolerance level above 50% in South America, Africa, and Asia, with the level being almost 100% in some Asian countries. There are large variations in lactose intolerance levels in the United States and in Europe. In Europe, levels range from 2% in Scandinavia, with levels also being very low in the United Kingdom and Ireland, up to 70% in Sicily. In the United States, lactose intolerance levels vary because of ancestry. White Americans have a lactose intolerance level of 15%, African Americans, 80%, and Mexican Americans are 53% lactose intolerant. (Vesa 2000) Northern Europeans would have ingested milk on a regular basis because of the nutritional value. If someone in the group was not able to digest lactose, they would not have gotten the same nutrients as their neighbors. If the majority of the group was gaining sufficient nutrition from the food they were all eating combined with the milk in their diet, there would be little reason to come up with something so that the lactose intolerant people would be able to get the same nutrients. Therefore, those who were lactose tolerant were more likely to be healthy and survive to reproduce, and be chosen by the opposite sex to reproduce, and pass along their genes. Areas where inhabitants would be able to obtain sufficient nutrition from things other than milk would not need to be lactose tolerant, so there would not be any advantage to having the gene, so it would not spread through the population. In populations in arid regions, like northern Africa and parts of Asia, lactose tolerance would have decreased the risk of dehydration, whereas if those who were lactose intolerant would be increasing their risk of dehydration due to the effects of the lactose intolerance. In European populations, lactose tolerance could have contributed to proper bone growth and decreased chance of rickets, along with enough vitamin D.

One trait that definitely evolved through natural selection is skin tone. There is a strong chance that lighter skin tones could have evolved due to the risk of vitamin D deficiency, since vitamin D is most often created by the body from sunlight or obtained through food. Populations far from the equator and closer to the poles have lighter skin tones than those closer to the equator. Since there is a greater concentration of UV rays at the equator than closer to the poles, people near the equator can have darker skin and still take in enough sunlight to create enough vitamin D. People living closer to the poles would need more time in the sun to get enough vitamin D. (Mielke 2006) The combination of the lower concentration of UV rays and the fact that its colder as you move away from the equator, people evolved lighter skin tone to be able to take in more sunlight in a shorter period of time. A possible reason for darker skin tones is that the layer of melanin can be a shield from the sun, so as to decrease sunburns (Barsh 2003). While skin color may or may not be a factor in who a person would reproduce with today, at the time when variations in skin color evolved, there would not have been a great enough difference between skin colors in any given region, so there would not have been very much, if any sexual selection for skin color.

Linkage disequilibrium is defined as two genes that are found close to each other more often than would be predicted by chance (Mielke 2006). This can be due to the lack of time for recombination to occur or to natural selection. One hypothesis is that the linkage disequilibrium is a product of natural selection. It may be more advantageous to the population to have both genes rather than one or a combination of both. It has been found that having two specific HLA genes can be helpful in avoiding some infectious diseases and autoimmune disorders. Another hypothesis is that the genes do not have enough time to recombine. Two populations come together and combine. All of the offspring have both genes and go on to reproduce. One hypothesis as to why we see the linkage disequilibrium is that there was not enough time for the two genes to combine together.

Admixture has greatly influenced linkage disequilibrium. It allows many different genes to come together. Since it is widely accepted that linkage disequilibrium is caused by natural selection, it is helpful to have more different genes to enter a population’s gene pool. When people of multiple cultures come together, there is a combining of genes. It is possible that this combination can be advantageous to the offspring.

Many traits are almost impossible to determine whether they are due to natural selection or cultural preference, because so many can apply to both categories. Most traits that can be attributed to sexual selection, such as lactose tolerance or intolerance, also have some evolutionary advantage that would let the individual survive longer to pass along their genes.

When early humans were hunter gatherers, there was a vast amount of gene flow across large areas of land. After agriculture, people were more sedentary, so there was less gene flow. The hunter gatherer lifestyle involved a lot of movement, so they were running into other groups of hunter gatherers. When two groups meet up, there is reproduction between the groups. Those offspring have traits from both groups of people. In agrarian societies, people reproduce with their neighbor, so there is less gene flow. This would also explain why there are some diseases that are distinctive to specific groups of people, such as the way Tay Sachs and Chron’s Disease are more common to Ashkenazi Jewish populations and Amish populations are prone to Ellis-van Creveld Syndrome (Marks, 1995). Without more genes entering the gene pool, unwanted traits can build up. Also, in agrarian societies, people tend to live very close together, which makes the transmission of infectious diseases very easy. Those able to resist the diseases, or survive them, were able to subsequently reproduce and pass along their genes to the next generation. Most traits are selected for due to both natural selection and sexual selection. In northern Europe, it was advantageous to be lactose tolerant because the population consumed large quantities of milk, but the lactose intolerant individual would not have been able to survive as long, thus letting the lactose tolerant genes be passed along. Both natural selection and sexual selection play big roles in human evolution.

Beginning in the middle of the 20^th century with the invention of computers, technology has been advancing at a significant rate and allowing for new capabilities and more powerful computations. Computers and their services are extremely pervasive, entering nearly every market and field in some capacity, whether it is for simple processing or for complex applications, algorithms and mathematical or scientific computations. The social sciences are included among these fields, and biological anthropology, given its combination of science and humanities, is a field that could greatly benefit from the potential of computing. In addition, new technologies have allowed for huge advances in the study of humans at the molecular level however they have also brought up several ethical issues along the way such as the potential effect of identifying genetic markers for diseases, the ethical implications of pregnancy terminations and more.

The use of computers in anthropology seems to have begun with Kunstadter et al in 1963 as described in “Demographic variability and preferential marriage patterns.” The study utilized computer capabilities for analyzing the data they collected (Dyke 1981:193). From that time, the use of computers has increased dramatically, particularly in the past decade with the technology boom as the world becomes increasingly connected and dependent on technology. In fact, I would even go so far as to say that the use of computers is almost expected by the general public, and with more focus being placed on studying the sciences it is inevitable that many things will become computerized and automated.

But the question the use of computers in biological anthropology raises is as follows: What effect will computers, and technology in general, have on biological anthropology? In some ways they will have a very positive effect, allowing for more precise calculations that can be performed quickly with great ease. But in other ways the introduction of technology could potentially harm the field. To what extent can computers be used to simulate populations, experiments, or biological models? What are the potential ethical implications of using technology to pinpoint genes? This discussion will address these questions and more as it explores the various uses of technology in biological anthropology.

As mentioned previously, computers first entered the field in the 1960s. However, at that time their use was somewhat limited. Before being ready for use, two procedures are necessary in order for a computer model to be used reliably in any study; sensitivity analysis and a validation test (Dyke 1981:194). Sensitivity analysis is essentially a test of consistency to ensure that equal and similar values entered into the model produce similar results, while validation is a test for correctness (Dyke 1981:194). Dyke claims the simulation model began as a graduate student’s project, however after creating the simulation the student found that “the task of phrasing anthropological questions to fit the model required as much time and effort, and certainly as much creative ability, as the computer programming done so far.” (Dyke 1981:193-194). The main idea behind this simple statement is that although the computer simulation can be relied on for computing quickly and performing as intended, this is only half of the battle. The challenge of incorporating technology into anthropology is figuring out how to do so in a way that will be beneficial and produce correct, applicable results. A huge benefit of computer simulations is that, as opposed to anthropological fieldwork in which it is not always possible to collect complete sets of data, simulations can produce “output which mimics real-world measurements as closely as one wishes, and which is ideally complete” (Dyke 1981:203). The caveat to this is that the data produced by these simulations cannot be guaranteed to be “natural,” and it must be acknowledged that there is a small margin of error and is merely close to what may be found naturally. Another positive benefit of using computer simulations includes the potential for reducing the need for using animals in biomedical experiments. Although complete replacement is unrealistic, computer simulations could reduce the number of animals needed for a given experiment, and, rather than scientists being limited by the number of animals they can perform tests on, they can perform thousands of theoretical tests in a short time-span (Summers 1998).

Some people may fear the idea that technology and computer simulations or models may take over biological anthropology, however I believe that these fears are misplaced. As long as researchers and anthropologists remember that a computer simulation is not natural, and the results must be taken with a grain of salt, then real experiments will continue and simulations will be used only as a supplement. Computer-aided computations pose no threat to the field, and simulations should not either as long as they are used as a supplement rather than in an attempt to replace real, “natural” experiments altogether. Computers and robotics can also be used to perform the more tedious laboratory tasks that can bog down researchers, and as a direct result of this, researchers can spend more time in analysis and drawing conclusions from their data. In addition, the data collected through computers and robots as a whole is more accurate and precise than data collected by a human.

Perhaps one of the most well known applications of technology in biological anthropology is in the field of genetics. Technology has allowed scientists to model the human genome and begin to pinpoint genes that cause various medical conditions and phenotypic characteristics. In some ways technology has had a positive impact on the field, however it has also had a negative impact.

With the ability to study genes, anthropologists have discovered that the environment plays a much greater role than previously believed, and that a person’s genome is not a direct blueprint for their traits. This knowledge has allowed for advances in biomedical research and the eradication of false notions that contributed to racism and eugenics, among other things. By understanding the gene-environment interaction, researchers can perform more complex analyses and more thorough tests on someone based on their ethnic background and surrounding environment, such as diet. Rather than simply studying one “race” or ethnic group and their genes, it is now understood that a person’s genes, as well as their environment, diet, social status, and other factors, play a role in their phenotype and in the expression of certain genes or prevalence of certain conditions or diseases. Studying genes has also allowed for the study of human origins through things such as mitochondrial DNA and y-chromosome DNA. This DNA has been tracked and different haplotypes identified which allow for people to learn about where their ancestors came from, which has the potential to break down racial barriers by showing that everyone is somehow related.

On the other hand, the ability to identify genes can potentially bring up various ethical questions. One such question involves the ability to identify genes that denote certain medical conditions, which in some cases may be fatal. This information could potentially lead to a person’s inability to obtain healthcare coverage or be otherwise discriminated against. If this sort of testing occurs, it brings up the ethical question of whether or not such tests should be required, because many people would rather not know what their future holds, and because of the aforementioned healthcare issue. Rabino conducted a survey that was mailed to 3,632 U.S. members of the American Society of Human Genetics, and 72% agreed with genetic testing for curable diseases, while slightly less (66%) agreed with genetic testing for not curable diseases. The ethical question this highlights is whether or not people with family histories of a disease should be tested for genetic markers even if the disease is not curable (Rabino 2003:369). It seems almost cruel to be obliged to inform someone that they have a high chance of developing a disease that cannot be cured, but in some ways this could, perhaps, help that person to better cope with the illness, if, for example, the illness was a late-onset disease. General medical practitioners who may be performing these genetic tests or receiving their results may also be ill-informed regarding the test and what it actually means, which can lead to confusion in patients regarding their potential risk for a disease or condition (Rabino 2003:374). As is the case with computer models, having the technology is not simply enough, but knowing how to use the technology and what the results actually indicate is key.

Another extension of genetic testing involves the ability to test for genetic markers of conditions in a fetus. Conditions such as Down Syndrome can be determined through genetic testing before a child is born, which could potentially lead to a parent deciding to terminate the pregnancy. For the most part, a majority of researchers considered the termination of children who would die of a disease by the age of four, develop a severe childhood disease, or be severely mentally retarded as an ethically acceptable termination (Rabino 2003:376). The major issue with deeming whether or not a termination is ethically acceptable is that the decision will undoubtedly vary from person to person, but it could potentially become difficult to distinguish between what is an ethically and what is not an ethically acceptable reason for the termination of a pregnancy. If people began to terminate a pregnancy because of a less serious risk such as being an unwanted gender or having only mild mental retardation, or simply because they found something in the genetic makeup of their child that they did not find desirable, then technology in the field will be used for a very unethical purpose. Rabino states, “In Aldous Huxley’s day and in his novel Brave New World, eugenics happened by government mandate; in this new genetic era, some writers ask whether it might one day take some kind of government intervention to prevent it.” (Rabino 2003:379).

Similar to the problem with uninformed medical practitioners delivering genetic test results to patients, the inability for the media to properly report findings leads to the general public believing incorrect things such as certain genes “coding” for behavioral traits when only a small correlation was found, or when extensive studies have not yet been performed. While this is not a direct effect of technology on the field, it is certainly related to it because the technology and science behind these findings is often too complex for the majority of the population, but simplifying the results of experiments in order for the public to understand them can lead to people believing things that are simply false. It is therefore possible that genetic findings could be construed in such a way as to provoke discrimination against groups of people because the public does not understand the result of an experiment.

Ultimately, despite these ethical issues, technology, on the whole, is a good addition to biological anthropology. While these issues need to be dealt with, I would argue that the benefit of being able to study genes and locate genetic markers outweigh most of the negatives. Medical care can be improved to allow for more personal care, and perhaps by understanding how some diseases interact with genes, cures could be found for things that are at present not curable. This technology has also allowed for more research regarding human origins which was previously not possible. The important thing is that technology be used for research, and not for deciding what is or is not “good” in terms of genes and conditions.

Technology and computers in biological anthropology have advanced the field in a number of ways. With computers allowing for simulations to be performed and experiments to be replicated on thousands of theoretical subjects, and complex mathematical models and computations being constructed and solved with great ease, computers have certainly made many things in the field easier to accomplish. Rather than being required to focus on the little things such as performing calculations or creating models by hand, the computer takes over these tasks and allows the anthropologist to focus on what is really important, developing new research questions and performing that research, and educating the public about their findings. Technology has also changed the face of genetic research completely, allowing for the complex relationships between genes to be, at the very least, acknowledged if not understood. Technology allows biological anthropologists to further understand the relationship between genes and the environment, learn more about human origins and much more, all with greater ease so that they can continue to make scientific discoveries for the benefit of all humankind.

Humans have complex rules of culture that dominate all parts of life from where someone will live to whom they will marry. Aural languages are the primary way in which these rules are taught and handed down by the older generation to the younger. Without a shared language it would be impossible to convey ideas and meanings that make up a certain culture. People also tend to stay close to those who share similar ideas and culture. Language can serve as a uniting force even when cultures are different, because language allows ideas to be communicated to others. Even if a person is placed in a new culture, the new rules can be taught to the recent migrant if there is a shared language.

Language plays a very important role in mating. Although there are always exceptions, generally only when a person has a fairly full understanding of the rules of society, and has become integrated into it, can that person find a mate and breed, thereby passing on the genes. Those who speak the same language are much more likely to mate then those who do not. In the event that a person cannot communicate with a potential mate it is very unlikely that a bond will form and offspring will be produced. Language also is an indicator of proximity. People who speak the same language tend to live in the same place. A human is much more likely to mate with someone who lives closer then one who lives farther away, simply due to convenience.

Like breeds with like and the more times that people of similar genetic backgrounds reproduce the less genetic variation there is in the population. For example, there is a greater frequency of Tay Sachs disease among the Jewish people who historically spoke Yiddish. These Jews were confined to certain areas of town and marriage with non-Jews was discouraged. There was little travel between the towns and everyone knew everyone else; they were most likely related to each other in one way or another. Choices in mates became slimmer due to the self-imposed, and externally-imposed, isolation of Jews to the ghettos. These Yiddish-speaking people would interbreed with each other. The common ancestor between two Jews was a lot more recent then between the Jews and the general population. The inbreeding in the ghettos, which continued in America, allows more easily for two carriers of Tay Sachs to mate and produce a homozygous baby.

Linguistics and genetics are connected through migration patterns. When humans migrated out of Africa and into Europe they brought their language and culture with them. Languages and cultures evolve and migrate just like people do. As migration continued and languages became more distinct from each other, people gravitated towards those whom they could communicate with. Living with those that you can communicate with is a basic survival strategy because common communication can lead to a shared knowledge of things like food and shelter. Life-saving information can be most easily shared through a common language.

In most species of animals, mate selection is a biologically-based phenomenon. But in Homo sapiens, it is both biologically and culturally based. Culture has a huge impact on mating practices and mate selection. Culture determines who is an acceptable mate and who is not. For example, in India, for many years people were only allowed to marry within their particular caste. (This is becoming an antiquated practice as the caste system slowly disintegrates.) This practice reduces genetic variation because there are a limited number of people within each caste. The longer members of a single caste interbreed with each other, the more likely it is that a negative recessive trait will become prevalent due to less genetic variation. This is also seen in royal lineages in Europe. Cousins were married to each other to keep the blood line pure. The problem with this is that hemophilia came to be very prevalent in these family lines. Cousins married each other so many times that a small mutation in the genome became a big problem in the family lines.

Mate selection is not only based on culture, language, and location but also the process of attracting the mate. Some people emphasize certain characteristics that are considered attractive in their society while others gain mates through wealth and shows of power. Those that rely on their looks often emphasize features that are linked to reproductive fitness.

There are many physical markers that lend themselves to what defines an attractive person. These physical traits usually indicate something that is advantageous to having children or passing on genes. Women emphasize certain features that make them appear younger and, therefore, better able to have children because younger women are in their reproductive prime. Women who have low waist to hip ratios are considered sexually attractive. This physical feature indicates a high estrogen to testosterone ratio, something that increase reproductive capabilities (Barber 395). Although the exact definition of an attractive woman changes from culture to culture the most general traits remain the same because of what they indicate about their ability to reproduce.

Men can use features such as their beards to show that they are better mates. Men with beards were generally found more attractive and appear older then those without beards. There is not much evidence available yet to determine why, but the hypothesis is that it has to do with testosterone levels (Barber 403). Normal amount of fitness and muscle mass is considered more attractive then the over-built muscles that are in fashion now. Normal muscle mass is more attractive than the over-built mass because muscles are expensive metabolically. There is a balance that must be struck between using precious energy and having enough testosterone to build the muscles (Barber 405). Those individuals with normal muscle mass are the ones who have successfully achieved this balance.

Charles Darwin was the one who first came up with the idea of sexual selection because he was not satisfied with his earlier theory of natural selection being the sole force behind evolution. Something else had to be driving evolution besides natural selection (Buss and Barnes 559). This second theory of Darwin’s, sexual selection, makes a lot of sense biologically. There have to be other traits besides those that are advantageous to survival that drive how populations evolve. There are certain traits that are considered attractive that have no evolutionary value, and may even be a disadvantage for survival. The classic example of this is the peacock. The tail of the male peacock is big and beautiful. There is no advantage to having this tail; it does not help the male survive better. In fact, this tail makes the male peacock more vulnerable to predators because the tail is heavy and impedes the peacock’s fleeing ability. In an evolutionary sense, the extravagant tail of the peacock should have been eliminated because of its disadvantage. The tail does persist though. This has to do with the fact that female peacocks find the bigger and brighter tails more sexually attractive.

This same concept can be applied to humans. Women are considered more attractive with larger breasts. However there is no evidence that larger breasts have any evolutionary advantage; they are not proven to produce more milk (Barber 412). If larger breasts do not provide an evolutionary advantage, why are women going to great lengths to make their breasts larger? They are considered attractive by men. Larger breasts do extract a price, however, such as back pains. This is only one example of a trait that has no impact on natural selection but does have an impact on sexual selection.

Understanding human mate selection is not a simple task. The genetics driving it are complex. But adding to the complexity are many non-genetic factors that have to be considered. Language, location, and culture are only a few of these factors. This may be one of the many parts of human diversity that we will never fully comprehend.

The study of the origins of populations has been a predominant aspect of biological anthropology. Since many peoples ethnic history often diverge from their actual genetic history, it has become difficult to actually pinpoint specific genes as markers for ethnic groups. However, in some cases a gene can serve as a great indicator for shared ancestry and can once again reunite populations which had been separated by past historical events. A perfect example of such studies is the study of the Cohen Modal Haplotype in modern Jewry. In Judaism, the Cohanim are the priestly class described in the Bible as performing the tasks of G-d in the Temple in Jerusalem. The line is said to be passed on through a patrilineal lineage tracing the line all the way back to the original haplotype found in the first Cohen, Aaron the brother of Moses. Scientists believe that they have found the exact group of genetic markers for the Cohen line on the Y-chromosome, identified as the J Haplogroup. The research of Thomas, et al. supported the hypothesis of high frequency of the Cohen Modal Haplotype in both Ashkenazi (European) and Sephardic (Arabic) Jewish populations (Thomas,et al.1998). Unlike the rest of the Y-chromosome, the pseudo-autosomal region does not recombine. Since the Y-chromosome is inherited patrilineally, it can be used for a patrilineal genealogy - similar to how the mitochondrial DNA (mtDNA) can help construct a matrilineal genealogy, since it is passed on by the mother (Skorecki, et al. 1997). This essay describes how the Cohen Modal Haplotype can be used, not only affirm the beliefs of existing Jewish Cohanim to an ancestor, but also to link supposed "lost tribes" of Israel with the contemporary Jewish community.

The phenotypic variation between the two main Jewish ethnic groups is believed to be in a large part due to the admixture between the Jewish population and the surrounding non-Jewish communities (Ritte, et al. 1993). Previous to the study conducted by Skorecki, et al., studies had been conducted to examine the genetic basis for this diversity among the Jewish population, using neutral mtDNA and Y-chromosome markers. However, the 1997 study was one of the first to examine the subsets of males comprising the Cohen priesthood line. In the Jewish community, there is no other basis for assigning to the priestly class other than tradition, by paternal descent. Being specified as a Cohen carries other connotations, including a ban on marriage with converts to Judaism and a ban on having sexual relations with a non-Jew. This type of cultural practice would keep a more "pure" lineage within a Jewish communal framework. Based on a survey of Jewish cemetery gravestones, it is believed that the Cohanim comprise about 5 percent of the entire Jewish population (Skorecki, et al. 1997). In the 1997 study, six haplotypes were identified from the DNA of 188 individuals from a worldwide Jewish sample, using the Polymerase Chain Reaction (PCR). Looking at the Y Alu Polymorphism (YAP) insert, it was found that a higher percentage of YAP+ chromosomes were found in lay-Jews than in the Cohanim. Among the Cohanim, it was found that there was a higher preponderance of the YAP-, DYS19B Haplotype in both the Ashkenazi and Sephardic populations. Since these two populations were separated for such a prolonged period of time, the fact that they have similar polymorphisms, at about the same rate, is quite striking. Skorecki, et al. (1997) suggested that this was possibly the founding modal haplotype of the Jewish priesthood.

Another study conducted the subsequent year by Thomas, et al. (1998), tested more SNP markers, as well as 6 Y-chromosome Short Tandem Repeats (Y-STR). They still found that a clear difference was observable between the Cohanim population and the general Jewish population, with many of the Cohen STR results clustered around a single pattern they named the Cohen Modal Haplotype (CMH-6). They also found that the Cohanim were most matched with the J Haplotype and were twice as likely to have all 6 of the Y-STRs, when matched with lay-Jews (Thomas, et al. 1998). They dated the origin of the haplogroup to approximately 3,000 years ago - around the time of the Temple period in Jewish antiquity - with variation depending on the length of the generations. However, the J haplogroups cannot prove Jewish ancestry, as it is also prevalent in the surrounding Middle Eastern populations (Nebel, et al. 2001). For non-Jewish populations with the CMH-6 matches, it is most definite that they are part of the J Haplogroup, but are not necessarily Jewish. Thus, even a full 6/6 (CMH-6) match for the 6 Y-STRs cannot solidify Cohen ancestry; it can only somewhat strengthen a previously existing belief, passed down through oral tradition. In relation to studies of other populations who claim Jewish ancestry, this is also the case. The Cohen Modal Haplotype may not be able to be used for definite Jewish origin, but it can prove origin within a specific region. For those who want to believe in Jewish ancestry, this may be proof enough.

The existence of a group of Ethiopian Jews has been recorded in the historical record for a long time. The first believed reference to the Ethiopian Jews was by a 9^th Century traveler named Eldad Ha-Dani. He appeared in Libya claiming to have journeyed from an independent Jewish kingdom in East Africa, though he seemed to not have astute knowledge of the geography of the area, which is why his account has become highly speculated (Kaplan 2005). The community had been referenced many times by Ethiopian Emperors who were hostile towards them, even trying to forcibly convert them. Emperor Yeshaq, ruling from 1414-1429 CE, is known for being the first to confiscate the land of the Ethiopian Jews and to give them the name Falasha, the term for a landless person (Kaplan 2003). Though it is a pejorative term, it has been commonly used to refer to the Ethiopian Jewish community. According to contemporary 17^th Century accounts these populations were practicing Jewish ritual. A Portuguese traveler by the name of Manoel de Almeida recounted that "the Falasha or Jews are of Arabic race and speak Hebrew, though it is very corrupt. They have Hebrew songs and sing Psalms in their synagogues" (Beckingham and Huntingford 1954). The presence of a Jewish people in Ethiopia was known for centuries, but the question was whether they could be proven to be genetically Jewish.

The Ethiopian Jews believe themselves to be the descendents of the Tribe of Dan, who left the Kingdom of Israel during the time of civil strife between the Kingdoms of Judah and Israel. This story was related to the Rabbis by Eldad Ha-Dani (the Danite) when he was found in Libya. This story is contrary to their epic tale, the Kebra Negast, which describes the Ethiopian Jews as descendents of the son of King Solomon and the Queen of Sheba - though none of them hold it to be true. Whatever the real story, the Ethiopian Jews believe that they have a connection with world Jewry, culturally, religiously and genetically. Initial genetic studies were quite disparaging for the Ethiopian community. Initial analyses of Ethiopian males living in Israel and Ethiopians living in regions located north of Addis Ababa, Ethiopia, have shown distinctiveness of the Y-chromosome haplotype distribution of Ethiopian Jews from conventional Jewish populations (Lucote and Smets 1999). Their relatively greater similarity in haplotype profile to non-Jewish Ethiopians is consistent with the view that the Ethiopian Jews descended from ancient inhabitants of Ethiopia who converted to Judaism (Zoossmann-Disken, et al. 1991). These Y-chromosome studies, however, refer to only a partial section of the paternal lineage. So while for the most part the Ethiopian Jews do not share the Cohen Modal Haplotype, there are still some cases of Y-chromosome connectiosn with other Jewish populations.

A study of intended for analysis of the DNA of Libyan Jews had included both Ethiopian and Yemenite Jews in its comparative populations. To the surprise of the researchers, the analysis had grouped together Y-chromosomes from both the Ethiopian and Yemenite Jewish individuals (Rosenberg, et al. 2001). The differentiation statistic and genetic distances for the Ethiopian and Yemenite Jews were quite low, among the smallest of comparisons that involved either of these populations (Rosenberg, et al. 2001). "Ethiopian Jewish Y-chromosomal haplotypes are often present in Yemenite and other Jewish populations, but analysis of Y-chromosomal haplotype frequencies does not indicate a close relationship between Ethiopian and other Jewish groups" (Rosenberg, et al. 2001). However, both linguistic and historical evidence demonstrate that Ethiopian and Arabian peoples have communicated with each other since at least the 6th century BCE. In addition, Yemen was ruled by governors from Ethiopia during 525–573 CE (Tobi 1999), so admixture between the populations may be likely. As will be shown later, other African populations have high frequencies of the Cohen Modal Haplotype; these groups also are believed to have come from a southern Arabia Jewish population. It could be suggested that due to frequent disruption of the Ethiopian Jewry, their genetic material has become more like their non-Jewish Ethiopian neighbors and therefore have lost the higher frequencies of the Cohen Y-chromosome. Though the genetic data has not definitively proven any connection between the Ethiopian Jewish communities with those outside, it is important to note that the reason it has been named the Cohen Modal Haplotype - because it is predominantly in the Cohanim. Since the Ethiopian Jewry did not distinguish any specific sub-group as particularly "priestly," it should be assumed that they should have the same frequencies as lay-Jews. Additionally, they should have an even lower frequency of the haplotype, when taking environmental factors, such as admixture with non-Jewish populations, into account. So though genetic analyses have not been able to prove much, all options are still plausible.

The Lemba are a group of Bantu speak Africans from southern Africa, mostly found in South Africa and Zimbabwe. What is peculiar about them is that they staunchly defend and identify themselves as a lost tribe of Jews who had migrated to South Africa (Parfitt 2000). The Lemba have held many traditions which are quite similar to Jewish tradition and custom, which include circumcision, a restrictive diet, ritual slaughtering of meat, and restrictions on marriage of Lemba to outside populations (Davis 2004). However, many of these traditions are also common of the Moslem community, which has been contact with that area of Africa for quite some time. For this reason anthropologists had rejected the idea of an actual connection to other Jews, and instead referred to the Lemba as a "Judaising African Tribe" (Parfitt 2003). The Lemba are a community of about 50,000 individuals who believe strongly in a traditional story of their migration to Africa from a place called Sena (Believed to be modern day Sana, Yemen). They also believe that they are the builders of an impressive archaeological site called "Great Zimbabwe." Until recently their claims had been unaddressed by the greater Jewish community or by the African communities in which they lived: there was recognition of the claims but no one addressed them. Finally, in the 1980's an anthropologist by the name of Tudor Parfitt came into contact with the Lemba and began to study them, as he had once done with the Falasha Jews of Ethiopia. After much study of the Lemba tradition, Parfitt began to believe that the tale of the Lemba could possibly be true, but he needed tactile proof (Davis 2004).

Recent studies had just been conducted on the Cohen Modal Haplotype on Jewish populations around the globe, Parfitt wondered if it could also be applied to the Lemba (Davis 2004). Parfitt obtained samples of Lemba DNA from the males, to send for analysis of the Y-chromosome. The study revealed that about half of the Y-chromosome samples retrieved from the Lemba, were Semitic in origin (Spurdle and Jenkins 1996). This was the biological proof for which both Parfitt and the Lemba were looking; following studies were conducted with much enthusiasm by the Lemba (Davis 2004). The significant similarities between the Y-chromosomes of the Lemba and that of Middle Eastern people, study solidified the idea that the Lemba were of Arabian origin. The Y-chromosomes of the Buba clan, considered to be the holiest of all the Lemba, were also tested, with remarkable results. Over 50 percent of the Buba had the Cohen Modal Haplotype, almost as high as the percentage of the Cohanim tested in an Israeli study (Davis 2004). This is especially important considering the higher status of both the Buba and Cohanim within their respective communities. From this Parfitt suggested that the Lemba did in fact derive from a Jewish population which inhabited southern Arabia.

The inclusion of the Lemba into the Jewish community has widespread ramifications. For one, it had been a long time theory that at some point the ancient Israelites were in fact Black Africans, the findings of another group with African phenotypes, but a Jewish genetic marker seemed to support this idea. Another point is that, the Jewish community is often perceived only as the Caucasian European Jews and other ethnic communities within Judaism were disregarded by the international community. The genetic ties of the Lemba with world Jewry gives more proof to the fact that Jews are not as atypical as they are portrayed and de-legitimizes the claim of Israel being a European colonizing state (Davis 2004 and Azoulay 2003). The anthropologist Laurie Zoloth writes that this study proves Jewish spirit of the Lemba, "a genetic version of a classic yearning of Jewish history [of] the long lost home" (Zoloth, 2003). Though, as Parfitt recognizes, there is a new found sense of Jewness among the Lemba, the genetic studies do not necessarily mean that the Lemba are indeed Jews (Parfitt 2002). The question remains about whether the Lemba feel enough of a Jewish connection to go the way of their Ethiopian "brethren," normalize their Jewish religiosity and move to Israel; or if they will stay in Africa and continue to practice as they always have. Though genetic tests are not always definitive, it may just be the spark needed to re-ignite a faltering flame. Correlation does not always equal causation; however, in the case of the Lemba it does look promising.

The Cohen Modal Haplotype, though not definitive for proving Jewish affinity, has become a highly accepted mode for correlation between the contemporary Jewish community and other communities who believe they have shared ancestry. In the case of Ethiopian Jewry and the Lemba, the existence of the Cohen Modal Haplotype, even on the slightest scale, can validate their feelings of Jewish ancestry. Truthfully, in my opinion, this is all that really matters. If a group truly wishes to be part of a community with which they believe they have religious, ethnic, or cultural ties, then they should be allowed to assimilate into that community. It is what is in the heart that counts and no piece of paper can say otherwise if one chooses to believe in their own tradition. By using Ethiopian Jewry and the Lemba as case studies, it is possible to see that connections of affinity can exist. This is especially the case in the Lemba, where the Buba are found to have about the same frequency of the Cohen Modal Haplotype as the Cohanim in the contemporary Jewish population. The separation of this clan from the rest of the Lemba is also quite reminiscent of the relations of the Cohanim in world Jewry. One thing is for certain, the strait between Yemen and Ethiopia has long been overlooked as a significant means for genetic transmission. Since both the stories of Ethiopian and Lemba traditions suggested migration through southern Arabian populations, admixture and gene flow between the populations is almost definite. Perhaps when looking at genetics and cultural traditions together, it can be easier to decide whether supposed affinities are true, definitely.

“Eugenics is not a panacea that will cure human ills; it is rather a dangerous sword that may turn its edge against those who rely on its strength.”

- Franz Boas

The term eugenics is derived from a Greek root meaning “noble in heredity” or “good in birth” but the fundamental principle behind eugenics is the future betterment of the human race. In real world application, eugenics is simply the deliberate intervention into the natural evolutionary processes that occur in the human species. A more detailed and complex meaning of the phrase has to do with the eugenics and its real life application throughout history especially in the first half of the 20^th century. Two criticisms of eugenics are that its intervention in natural processes is completely unnatural and that those who support eugenics movements and the other is that research projects are actually attempting to play “god.” The application and value of eugenics has been debated for a long time, but the fact is, eugenics is here and it cannot be hidden. Many countries all over the world are implementing some form of eugenics and there is no doubt that it is actually beneficial to someone’s plight. At the same time there is a dispute over its validity as a science and whether it is violates human and scientific ethics. The argument is eugenics corrupt, helpful, or do we not fully understand its true value as it relates to a larger evolutionary framework?

Throughout history, especially during the 20^th century eugenics has taken on many different forms. Many of these different versions of eugenics have had such a strong impact on society that just the very mention of them would bring tears to the eyes to the individuals who lived to survived them. Historically, the stigmatized reputation that eugenics is associated with is illustrated in many history textbooks within the chapter about World War Two. The holocaust was a form of eugenics that has been a scar on human society that the world has been trying to move past; however simultaneously not erasing from history because of the lesson it has taught us. On the other hand, other forms of eugenics have not done any harm to anyone and were actually very beneficial to certain individuals who were went through a more civil means too achieve their particular goal. For example, there are married couples who wish to have children, who are unfortunate enough to be genetically predisposed to certain ailments and illnesses. With the use of eugenics, technology can eliminate those chances of diseases being passed onto the offspring.

There have been many supporters of eugenics, just as there have been many detractors, even further there have been those have taken a neutral stance who want to see more advances. Even in 1916 in a journal article authored by world famous anthropologist Franz Boas, supported the philosophy behind eugenics. Boas felt that eugenics had two opposing points of view that would be in constant conflict with each other when it comes to certain issues. Boas feels that the fields of biology and anthropology both support eugenics but there is disagreement in how both sides interpret the eugenic philosophy.

Boas posed that biology is more concerned with an idea that function depends on form, that they seek an anatomical basis for form. For instance, that a more advanced civilization was due to a “…higher type; that better health depends upon a better hereditary stock and so on.” Whereas anthropology is more convinced that … “different anatomical forms can be adapted to the same social functions; [the anthropologist] ascribes; therefore, greater weight to the functions, and he believes that in many cases differences of form may be adaptations to different functions.” But Boas was very cautious with his analysis, even in 1916 when his essay was published; he was able to foresee what potential problems can arise from eugenics. He wrote that we should not use eugenics to make some kind of superman or super race, nor even use it ease any suffering or pain, but rather use it to prevent disease stricken offspring if at all, but until then just like any research or new technology it needs more testing and experiments before we can accept it.

For the detractors of eugenics, the phrase “The Road to Auschwitz went through Cold Spring Harbor” holds a lot of meaning in their argument. The significance of this phrase is that eugenics has been a negative in the field of science. Eugenics was supposed to be one of the greatest breakthroughs in history, but when it was carried out by certain historical figures it actually turned out to be one of the biggest disasters instead. Cold Spring Harbor Laboratory was one of the first institutes in the United States to carry out studies and research that had the idea of eugenics in mind, and it was actually considered the center of eugenics in the early 20^th century.

For those who do not support eugenics, there is a lot of evidence that would be very convincing for their argument. The terrible events at places like Auschwitz and the holocaust as a whole had the idea of eugenics in mind. The holocaust had the fundamental principles of eugenics in mind when the Nazi party was carrying out these violent and horrific actions, but the way it was applied through the mass-murders, and inhuman treatment of other humans was what captured the most attention. The Nazi party was trying to create a better race of human by culling the population of those who they saw as unfit, whether it was homosexuals, people who observe the Jewish faith, or those who had some kind of handicap whether it was mental or physical.

The phrase can be interpreted as the idea of eugenics, which was perpetuated by the Cold Spring Harbor Laboratory inadvertently influenced and supported the idea that the Nazi party had to help create their Aryan super race that they wanted to badly, and possibly without the Cold Spring Harbor Laboratory history could have been different but to know that is impossible. Now, it is important that the study of eugenics is not repeated again like it was previously. To defend this argument, it is not entirely fair to blame the failure of eugenics on Nazi Germany, certainly it was validated through the Nazi party but when examined more critically, those actions carried out during the Holocaust was more racism and intolerance than eugenics (Marks, 1995).

Now, with the arrival of the Human Genome Project a whole new chapter in the genetics field has opened up. Now, genetic modification can be seen as a form of eugenics, but in contrast to early 20^th century history it is not anything like it was in Nazi Germany but it is actually more helpful to in certain cases when examined on an individual case-by-case basis. Those in need of special help are in support of eugenics and the technology that has arisen because it has given individuals a choice to change a prospective offspring’s chance of inheriting an ailment from a parent.

Modern Eugenics has allowed for individuals to selectively erase certain undesirable genes, such as a gene for alcoholism or a cancer that the offspring would be likely to inherit. Still, there are critics who feel that this would lead to another instance of trying to erase a portion of the world’s population because this could ultimately lead to behaviors like selective abortion (Kerr et Al., 1998). This new selective breeding has been met with some controversy, because those in support argue that it is up to the individual to choose whether they want to help their children from becoming afflicted with the disease, and it is still met with the same defense about intervening in a natural process that should not be interfered with.

Also, currently there is another sect that stems from eugenics, named liberal eugenics. Instead of thinking of ways to better the human race, liberal eugenics is more concerned with the improvement in quality of life and well-being of an individual not only when it comes to biological characteristics but also biological capacities. In other words, liberal eugenics can enhance an individual’s physical capabilities, like being good at math or an instrument. One of the aims of liberal eugenics is to help parents produce prospective offspring that will in someway be more productive in some capacity.

In contrast, there are very many critics of this movement. One of the criticisms is that children who are “programmed” to be amazing at a particular sport will not only have the burden of shouldering his or her parent’s expectations but their own body’s expectations, which many feel is worse than having the most authoritarian parents (Prusak, 2005). There is still much debate on whether liberal eugenics is ethical or not, but it seems to be garnering more support, while at the same time they are having more doubters as to whether this is still within the realm of “playing god” and that it no different than what we have seen in the past in regards to some of the horrific historical events that are associated with eugenics.

Overall, this new form of eugenics when met with a lot of hesitation there was an interesting explanation in its correct context, that eugenics can be understood in a way that would explain its historical infamy while at the same time shedding some light on its value. In their 1998 journal publication, Kerr et Al. wrote that eugenics was first publicized as being unscientific, that it is technically unrealistic to meet the ideal goals of eugenics, totalitarian regimes were using abusing genetics by way of eugenic practices, and eugenics is altering the gene pool, where it is actually helping people on an individual case-by-case basis.

Eugenics has had a terrible of reputation for committing some of the most horrific crimes in the past century. Eugenics was aimed to help the human race, and hopefully eliminate certain deficiencies that the human species suffer from. Eugenics is a philosophy that is open to interpretation to any one individual and it should not be the scapegoat for what people are trying to achieve in today’s society. It is true, that the process is unnatural because of its intervention in what should be naturally occurring process, but at the same time on an individual level it would be extremely beneficial to those who need it more than most. The use of eugenics will constantly be under debate but it does not appear to go away anytime soon as there is more and more support for it. Until then, just like anything under constant debate and scrutiny there needs to be more research done until we can come to an understanding of what eugenics true value really is. As Franz Boas said at the beginning off this essay, it can be a dangerous sword that will turn its edge on those who try to rely on its strength.

Keywords: Melanin, Skin Pigmentation

Found in all living kingdoms, melanin is produced by the amino acid tyrosine and plays a vital role in the human body. It can be found in the skin, hair, and brain, and has multiple functions, but it is difficult to understand the relationship it has with different organs. But, the question that plagues researchers is the origin of light and dark skin. In the skin, the amount of melanin is dependent on genetic and environmental factors, and aids in protecting the skin from harmful ultraviolet rays. The lack of melanin or the presence of too much can result in health complications. In the rest of the animal kingdom, melanin is useful for protection against environmental factors. Melanin is an essential compound in the living kingdoms.

Two theories exist on the origins of skin pigmentation. The first theory believes that the lighter skin tones emerged after the spread of humans about 100,000 to 150,000 years ago (Lao et al. 2007). As humans left Africa and settled the in other parts of the world, the skin lost the need to be dark because the sun’s rays were not as damaging further away from the equator. The second theory believes that lighter skin tones were present prior to “Out of Africa” (Lao et al. 2007). Here, lighter skin tones could have developed through mutations or environmental changes. Groups could have move away from the equator to settle farther south in Africa, and reducing the need to have darker skin. From these lighter skin tones, even lighter skin tones could have developed after human movement away from Africa. Researchers are still looking into if the light pigments evolved independently in different populations. Current

research has shown light skin color is derived from dark skin color, and independently arose in Europe and Asia, while dark skin color reflects the ancestral skin color (Lao et al. 2007). Here, melanin is a vital component to the variation found among humans.

Three kinds of melanin exist in humans; they are eulmelanin, pheomelanin and neuromelanin. Eulmelanin is found in hair and skin, and codes for black, brown, yellow and grey pigments. It is found more abundantly in darker skin, and there are two types of it—black and brown. Small amounts of black, in the absence of other pigments, causes hair to turn grey. Small amount of brown, in the absence of other pigments, results in blonde or yellow hair. Pheomelanin in found in both men and women, but women generally have more. This causes women to have skin with more pink tones because of its pink to red hue range. In hair, pheomelanin causes red hair. Neuromelanin is a dark pigment found in the brain, but these areas gain pigmentation as the individual matures into adulthood. The function of these pigment areas is not known, but the loss of pigment results in neurodegenerative diseases including Parkinson’s disease. Also, in advanced Alzheimer’s disease, a loss of the pigment synthesizing chemical norepinephrine has been known to occur (Stefanato et al. 1997).

Parkinson’s disease affects the central nervous system and impairs speech and motor skills. Parkinson’s disease is an outcome of a decrease in neuromelanin in the brain, which leads to a decrease of dopamine synthesis. The decreased amount of dopamine in the body results in decreased stimulation of the motor cortex of the brain. Similarly, as Alzheimer’s advances, the body slowly loses control over bodily functions. One might conclude that the loss of pigment in the brain directly corresponds to the amount of control one has over motor skills. It is important to understand how the body reacts to the loss of pigmentation because although most cases of Alzheimer’s and Parkinson’s do not reflect any kind of familial inheritance, the chances of having one of these diseases is increased when a family member has it. Most genetic forms of Parkinson’s are the result of mutations in the DNA, which can be passed on to future generations (Lohmann et al. 2003).

Despite the negative aspects of the lack of melanin, the presence of melanin protects DNA from mutations caused by ultraviolet rays. Closer to the equator, people have more eulmelanin in their bodies. This makes their skin darker and protects the skin from the higher levels of exposure to the sun. Having darker skin gives people an advantage because they are less likely to suffer from sunburn or from melanoma, a potentially deadly skin cancer. In contrast, high levels of eulmelanin in light skinned individuals can result in melanoma. The high levels also lead to a higher disposition to a vitamin D deficiency in areas that receive less sunlight than the areas near the equator (Parkin et al. 2005). Vitamin D deficiencies result in several bone diseases, including rickets which affects the growth of long bones in children. Other diseases pertain to density and fragility of bones in adults (Rajakumar 2003). This problem with vitamin D deficiency has been corrected with vitamin D supplements in food products (Grant et al. 2005). Melanin not only protects the skin, but it protects the eyes from the damaging ultraviolet rays of the sun and from high-frequency visible lights. Melanin plays a vital component in protecting the body from harm from the environment.

In the rest of the living kingdom, melanin protects plants and animals from harmful things in the environment. Melanin acts as an immune system eliminating foreign pathogens in invertebrates, which is similar to how melanin isolates toxins in the human body in order to protect the rest of the cell (Cheun et al. 2004). It also helps prevent cell degeneration caused by solar radiation in fungi and bacteria. Current research has shown that some fungi use melanin to harness gamma rays and convert the energy and use it for growth of the fungi (Dadachova et al 2007). Another use of melanin is as a defense mechanism. For example, the Common Cuttlefish ejects a form of eulmelanin to protect itself from predators. This illustrates how melanin is useful in other life forms, and has similar functions in protecting the organism as it does in the human body.

As previously illustrated, melanin has many uses in the human body, as well as in other organisms. Without melanin, the radiation from the sun would have more damaging effects on the body, not to say that is not already damaging. From the earliest Homo sapiens, melanin has been a build in adaptation that protects the human body from serious harm from the surrounding environment

We the human race have classified most life on this planet. From the smallest microbes to the largest animals, we have been able to classify almost every single one of them and their variants. The system we classified them by goes by kingdom, phylum, class, order, family, genus, species, and subspecies. With this classification system, we have been able to categorize every living thing. Humans would fall into this system like this:

Kingdom: Animalia, Phylum: Chordata, Class: Mammalia, Order: Primates, Family: Hominidae, Genus: Homo, Species: Sapiens, Subspecies: Sapiens (Jackson, 2007, 72) However, that’s as far as humans can be classified. All other life forms can be classified further but humans. There are many variations of Homo sapiens yet each one doesn’t have its own distinct classification. Clearly there is significant variation among Homo sapiens. For instance, you can’t say a man from Ireland is the same as a man from Africa because the differences are so obvious. Both are physiologically, biologically, and culturally different from one another. A man from Ireland has really light-brown or peach color skin, whereas a man from Africa has definitively brown skin color. The hair of an Irishman is also very different from that of an African man. Although both are Homo sapiens, scientifically they are both designated as Homo sapiens despite the difference between the two of them. The Irishman isn’t designated differently from the African man, scientifically the Irishman is classified as Homo sapien and the African man is also classified as Homo sapien as if they were exactly the same. That would be like saying that a tiger is the same as a lion. Both may be big cats, but both are distinctly different from one another and are given different official names. So why is it that the variations between human beings aren’t classified or given any kind of scientific designations? Surely there’s way to classify all the variations of human beings there are on Earth and group them into specific categories or give them specific names to set them apart from each other and account for their differences between them, just as we can with all other forms of life, isn’t there? The answer is no. For centuries, scientists have tried to do so, and they still haven’t come up with one.

Many centuries ago, when the Europeans began to explore the world, they encountered many different kinds of plants, animals, and human beings. The scientists in those early times sought to name and classify the great diversity of life in the world. The reason why is because:

“Human beings seem to understand their world more easily by creating classifications for lots of things,..”(Mielke, 2006)

The varieties of humans there were in the world were no exception to this. Francois Bernier (1620-1688) was perhaps the first to try to classify the variations in humans. In 1684, Bernier stated that there were four or five races or species of humans. He listed them as: Europeans, Africans, Asians, and Lapps. He had also stated that the Africans of the Cape of Good Hope seemed to be different from the rest of the Africans, and this is probably why he said there were four “or” five races or species instead of one or the other. This was perhaps the first attempt to classify the human race ever documented.

In the 18^th century, some scholars believed human beings could be classified the same way as could a cat, dog, ape, lizard, bird, etc. Other scholars believed that human variation was part of the “Great Chain of Being”. The Great Chain of Being was basically the idea that god had created every single species of animal and plant that could exist and each living thing was placed in a one-dimensional hierarchy, each living thing being in a position higher or lower than another, going from the lowest form of life to the highest and most perfect species of human at the very top. Other scholars believed that the diversity of humans was the result of natural forces acting on the human race over the last 6000 years of its existence.

Carolus Linnaeus (a.k.a “the great classifier”, a.k.a”the father of systematics”) (1707-1778) came up with a two-dimensional hierarchy that opposed the one dimensional Great Chain of Being. In Linnaeus’ system of classification, animals were placed in classes which were then subdivided by order, then by genus, they finally by species. The classes (ie: mammals, reptiles, etc.) were large, broad categories that placed “types” of animals in equal rank relative to one another rather than one above the other. In the Great Chain of Being, species were just higher or lower in relation to other species where as with Linnaeus’ two-dimensional hierarchy; species were members of ever more inclusive clusters. Every species was a member of a genus and thereby a member of an order and thereby a member of a class. This system made everything systematic and orderly unlike the Great Chain of Being. In Linnaeus’ system, humans were classified along with the primates. Linnaeus went further to classify humans because sought to classify the varieties of humans. He grouped humans into four varieties based on color, geography, posture, humor and customs. The four varieties were American, European, Asian, and African. However, Linnaeus’ classification of humans received a lot of criticism because it was said to be based on broad generalizations about culture and utilized socio-cultural criteria that only slightly correlated with geographical criteria.

Linnaeus had a student by the name of Johann Friedrich Blumenbach (1752-1840) who came up with a similar classification system. Unlike that of his teacher, Blumenbach’s system was based more on cranial morphology rather than geography. He classified five types of humans, which were Caucasian, Mongolian, Ethiopian, American, and Malay. These five were divided based on the shape of their skulls, of which Blumenbach had a vast collection of. Blumenbach believed that humans were created in one place and then spread across the planet and that exposure to various climates and environments and having to adopt different ways of life to cope had over time shaped humanity into the various races that exist today. He had suggested that differences in customs and ways of life, variation in culture in other words helped to shape the features of the skull. Because of this, he thought that racial classifications wouldn’t work because variation in race could be changed over time by moving to a new environment and adopting new ways of life. The significance of this classification system is that it was based on empirical data rather than speculation about variations based on the accounts of travelers and secondhand observations.

During the 17^th and 18^th centuries, classifications of the human race were becoming more typological and ethnocentric in nature. Scientists were using cultural values, ethics, and preconceptions of their time in their classifications of human beings. These classifications linked behavioral traits like morals, values, and temperament to physical traits. During this time, ideas of distinction between “civilized” and “savage” peoples and “progression” gained scientific support. Many classifiers believed in the unity of humans and that the “savage” peoples could be improved. The classifications of this time placed human beings into the same natural order as all other living things. Physical characteristics and behaviors of other peoples that were regarded as “inferior” were thus deemed by scientists as traits that God had deemed these people to have or “God-given” so to speak.

However, some opposed these classifications. One of which was Reverend Samuel Stanhope Smith (1750-1819), a professor of moral philosophy at the College of New Jersey which is known today as Princeton. Smith opposed the theory of cultural evolution and believed that human beings were one species and descended from Adam and Eve as depicted in the Bible. He also believed that climate, society, and culture were the causes of the physical changes in humans which led to the diversity of humans we have today. Smith rejected the validity of racial classifications and suggested that it was impossible to precisely classify the various types of humans and that it was pointless venture. This is perhaps one of the earliest rejections of the concept of race.

During the 19^th century, scientists were trying to quantify and measure aspects of human bodies, mostly focusing on cranial morphology and using this to base their classifications of the human race. Using rigorous measurements as basis for classifications were regarded as being more accurate and scientific than the assumptions and analyses used in past centuries. A scientist focused this quantitative research on skull measurement because they believed that skull shape was resistant to change and therefore was seen as a very useful feature for determining a population’s and an individual’s ancestry and origin (this of course being incorrect). It was thought that by comparing variations in skull morphology, human variation could be objectively studied and human groups could be differentiated. Some scientists even went so far as to suggest that behavior and social status were associated with cranial morphology.

In 1900, the ABO blood group was discovered which eventually led to studies of the worldwide distribution of the blood types. This in turn led to data regarding the frequency of A, B, and O blood in diverse populations throughout the world. Scientists gathered these results together and started to analyze them. Two scientists, both with the last name Hirschfeld, proposed that the A, B, and O blood groups could be used to identify biochemical races. They then created a “biochemical race index” that identified three types of humans: European, Intermediate, and Asio-African. In 1925, a scientist named Ottenberg used the Hirschfelds race index and ABO blood group data to come up with six primary types of humans: European, Intermediate, Hunan, Indomanchurian, African-South Asiatic, and Pacific American. In 1926, another scientist named Snyder used the similarities in the frequencies of the ABO blood groups to come up with seven racial types that were similar to those of Ottenberg. These were European, Intermediate, Hunan, Indomanchurian, Africo-Malaysian, Pacific-American, and Australian.

During the first part of the 20^th century, scientists continued to come up with racial classifications. Some however began to argue that it was difficult to classify human beings into groups using zoological nomenclature like with all other animals. The reason was that unlike animals in the natural world, humans were shaped not just by natural factors but also by cultural factors like social institutions, religion, and language. This was said to cause complications that made the classification of humans a futile endeavor and an incorrect way of examining human variation. A scientist by the name of Montagu had argued against the use of the term “race” to classify humans, saying that “race” had lost its usefulness for describing human variation because “race” was being based too much on non-biological evidence and stereotypes. Montagu admitted that there were noticeable differences in human populations but also pointed out that there weren’t any clear boundaries in regards to variation between humans.

In 1950, an immunologist named William C. Boyd, proposed using gene frequencies to classify humans, saying it’s both objective and quantitative. He had come up with six races based on gene frequencies: Early European, European, African, Asiatic, American Indian and Australoid. In 1958, Boyd revised his classifications and came up with even more races than he did in 1950 and these were: Early Europeans, Lapps, Northwest Europeans, Eastern and Central Europeans, Mediterraneans, African, Asian, Indo-Dravidian, American Indian, Indonesian, Melanesian, Polynesian, and Australian. In the later half of the 20^th century, scientists proposed that geographical variation of traits in humans or “clines” should be studied to classify human beings. Clines took the place of races as the focus of study for many scientists during the 1960’s and 1970’s

Today among anthropologists, there is no agreement on how many types or species of humans there are nor is there any agreement on any kind of classification system. The following are some of the reasons why:

1. Human groups are not morphologically homogenous.

2. Many polygenic traits are difficult to measure accurately.

3. It is difficult, if not impossible, to determine discrete boundaries in continuously varying traits.

4. The traits used in a classification may be undergoing different rates of evolutionary change.

5. Traits are not linked.

6. How many should one use? Are three sufficient, or are 25? Would 32 be better? Or, even better yet, one could use 247.

7. If there are differences between groups, how much difference is biologically significant (10%, 20%, 31%, or 62%)?

8. Not everyone can be placed in a category. What does one do with those people who simply do not fit neatly into a group?

9. There is actually greater genetic diversity within groups than between major geographical divisions.

(Mielke, 2006, 19)

All this in mind, there is really no way to classify all the various types of humans there are like we can with all other forms of life. That reason being is that there is just too much variation between humans to classify. Any classification system used can’t seem to account for all the variations in humans. The diversity of human beings is just too great to divide into particular groups because you would end up with too many groups to keep track of and that number would keep growing because new variations are being discovered all the time, so classifying humans is basically a pointless and futile venture.

Our cells are different. Our skin cells are different from our liver cells. Our brain cells are different from our immune cells. But they all share the same genes. In each of our cells –estimated in the upwards of 10 to the 13^th power per person – cram almost 2 meters of nucleic acids, containing all the instructions for all of life’s functions. Each cell contains all the same DNA. So how could our cells be so different? How do cells making up our skin know to grow hair? and our cells that make up our brains transmit electrical signals? At least part of the answer is epigenetics.

Your genetic material is not just DNA. Your DNA is associated with structural molecules, replication proteins, repair proteins, and very important signaling molecules. These signaling molecules are a kind of tag on the DNA which can cause conformational changes that lead to changes in gene expression. Scientists call this the Epigenome, which translates to “above the genome.” These tags are made from organic matter and environmental factors can have a direct and profound impact on the epigenome. Introduction of a toxin that degrades the tag or the tag itself can have an effect on how a gene is being expressed [1]. Epigenetics does not change the sequence of the DNA, it only turns genes on and off by changing structural components.

Just a few years ago, people would only talk about the environment influencing our biology in abstract terms. But today scientists are developing ways to see epigenetic differences and they are finding that the environment can have a huge imprint. As noted above, epigenetic differences play an important role in cell differentiation. But, the specificity of these changes can be much greater than previously thought.

In fact, changes in your epigenome happen in your body regularly. During an immune system response to a pathogen, T cells are activated to perform specific functions – like kill infected cells or help B cells create antibody. But when T cells proliferate (reproduce) something amazing happens. The daughter cells perform the exact same function as the parent T cell. Somehow the instructions for the activated phenotype have been passed on to the daughter cells. It is thought that these instructions can be found in the structure of the epigenome – in this case methylation or glycosylation patterns on the genes which get passed on to later generations [2].

If you take two identical individuals, like say identical twins, you will find that over the years they become more and more different. In fact, that is exactly what recent epigenetic research has been showing. The epigenomes of these individuals deviate over time because of differences in lifestyles and experiences. This concept is called the Norm of Reaction. In other words, any one set of genes has a range of phenotypes depending on the environmental factors. Epigenetics and the things that influence the epigenome will influence where in that range the phenotype falls.

Physical height is a great example of the norm of reaction. A person’s genes play an important role in determining his or her height. But those genes only provide a norm of reaction. A person with a healthy diet, full of protein and nutrients will be much taller than a person without access to quality food. One molecular mechanism for this difference is epigenetics.

This knowledge can help us address other complex traits such as those that contribute to behavior. Intelligence, for example, is an extremely complex trait. No gene, not even a set of genes, can be said to be responsible for someone’s intelligence. In fact, most normally developed brains carry the same capacity for intelligence – all have the same norm of reaction. The only real factor contributing to intelligence is education. Environmental factors like education can contribute to epigenetic changes that can strengthen neural connections in the brain.

Angelman syndrome is a neurological disorder caused by a deletion in chromosome 15. Characteristics include intellectual impairment, seizures, speech impediment, and an unusually happy temperament. However, the same exact deletion in chromosome 15 causes a second disease called Prader-Willi syndrome. In Prader-Willi syndrome, the patient has mostly normal brain function, but experiences an uncontrollable appetite and are often of small stature and obese. So how could the same deletion on chromosome 15 cause two very different diseases?

It turns out that the epigenome is probably at play. People with Angelman syndrome have the deletion in the chromosome that came from the mother, while the people with Prader-Willi syndrome have the deletion in the chromosome that came from the father. This is called genomic imprinting and is most likely epigenetic in character. Although the exact mechanism is not yet known, the epigenetic markers on the chromosomes coming from the two parents must be different and must be inducing the two phenotypic differences. This difference in phenotypes is a strong example of the profound effect our epigenome can have on our lives.

You are, in fact, what you eat. You are even what your parents ate. Researchers at Duke University have recently shown that the diet of the parents can have a direct effect on their offspring. They fed normal mice an environmental toxin and found that it disrupted the epigenome of the offspring – changing DNA methylation patterns. The offspring with disrupted epigenomes had yellow hair and were very obese. This trait was passed on to the next generation. However, when the large yellow mice were fed a diet rich in methyl groups, their offspring reverted back to a normal and healthy phenotype. This demonstrates that epigenetic markers can have a profound impact on health and that that impact can be passed on to progeny [1].

More and more research is showing the importance of the Epigenome during the development of an organism. Some research as even suggested that parenting can have direct epigenetic effects. Mice that were taken care of when they were young had very different epigenetic markers than those mice that where neglected. Scientists have also showed that the ones with epigenetic markers like those raised with affection were much less aggressive. They continued to show that changing the epigenetic markers in badly reared mice could also reduce aggressiveness.

It is much less evident what these advances mean for humans, but it is clear that our actions have a direct impact on our genes and how they are expressed. More and more we realize that the sequencing of the human genome was not the end and that human biodiversity cannot be summed up by our genes. We are constantly influencing our genes and our lives by what we eat, what we drink, and how we treat one another.

Anthropology is a diverse field, filled with just as diverse a variety of methodologies. However, the focus of certain anthropological methodologies, such as archaeology primarily rests with artifacts, that is to say, inorganic man-made materials left at a site by the bygone community being studied. There is no doubt that the archaeological record has gained incalculable boons from studying these artifacts. However, inorganic materials – pot sherds, burial beads, pieces of clothing have a limited scope when it comes to their voice in history.

Fortunately, the voice of inorganic artifacts is just one of an entire chorus archaeologists can use to learn about the site being studied. One such voice can be heard from biological remains left by the actual individuals who lived on the site. The use of biological remains is referred to as bio-archaeology.

“Bio-archaeology is a rapidly developing anthropological specialization in which researchers integrate osteological data from archaeological collections of human skeleton remains into comprehensive reconstructions of past human health, behavior, and population history.” (Buzon et al. 871) As the quote from the Handbook of Archaeological Methods states, these bones, like the clothes that once covered them, like the pots they once carried, like the beads they were buried with are essential to aiding archaeologists in their research. Human osteology as an archaeological methodology is one that should be employed at every applicable site.

Osteology as a whole is a very broad discipline, so to illustrate its many uses in archaeology, different sub-methodologies must be addressed to unify it as a whole. For example, certain bones recovered on an archaeological site can give the researcher insight into the sex and age distribution of the population. The most notable bones employed for this technique are the innominates, or the hip/pubic bones. An archaeologist can gain more information about a population that possibly any other bone that could be recovered.

The American Journal of Physical Anthropology comments on the usefulness of studying the hip/pubic bones in archaeology. “The pubic bone is the most reliable sex indicator in the human skeleton,” (Walker, 385) writes anthropologist Phillip Walker. In the article “Greater Sciatic Notch Morphology,” Walker demonstrates a system for determining the sex of an individual by measuring the width of the sciatic notch in the hip bone, and assigning it a score.

Walker produces the following results: “There is very little overlap between males and females at the extremes of the scoring system. About 90% of the people with scores of 1 (a wide sciatic notch) are females. At the other extreme, about 90% of the os coxae assigned scores of 3 or greater (a narrow sciatic notch) are from males.” (Walker, 387) What Walker’s data means, is that a skeleton with a wider sciatic notch is most likely a female, and a skeleton with a more narrow sciatic notch is most likely a male. As with all measurements there is a degree of error, but this system allows even archaeologists with no formal osteological training to fairly accurately identify the sex of a skeleton at a site.

Along with sex, the relative age of individuals found at a site can be determined through osteology as well. Much like the pubic bones, there are several parts of the skeleton that help to determine age. One would think that the most obvious way to tell the age of a skeleton is by simply looking at the size of the bones. However, this is not the case. Bones can be fragmentary, they can be underdeveloped or could have belonged to an individual with a metabolic disorder. There are many reasons why a skeleton could have large or small bones, without these bones correlating with the age of the skeleton.

One way to determine the true age of a skeleton is to look for bone-fusion. When we are born, the skeletons that support our organs in our later years are little more than lumps of cartilage. As we grow, the process of “ossification” also known as bone growth takes place. Authors of The Human Bone Manual Tim White and Pieter Folkens explain this process well. They write, “During growth, the roughened, porous, usually irregular end of an immature long bone’s metaphysis marks the region at which most longitudinal growth occurs. Sandwiched between the metaphysis (the primary center of ossification) and the epiphysis (the secondary center of ossification) during development is a cartilaginous center known as the growth plate (epiphyseal plate), a tissue layer responsible for bone formation. This plate, a layer of cartilage, “grows” away from the shaft center. The growing cartilage is replaced by bone on the diaphyseal side of the plate. Ossification and growth of the bone come to a halt when the cells at the growth plate stop dividing, and the epiphysis fuses with the metaphysis of the shaft.” (White and Folkens, 46-47)

What this means, is that more of our bones fuse together the older we get. This is a crucial key to understanding and analyzing skeletal remains. This means that even if bones are very slender and small, but they are fused, they belonged to an adult, and the reverse is true for large, un-fused bones. Bones do not all fuse at the same rate either, which is also important to understand. If the radii are fused at the wrists, but the clavicles are un-fused at the sternum, an archaeologist can know that the individual was not a mature adult at the time of death. Even small, usually discounted bones are valuable in this area. The hyoid bone, a parabolic bone of the throat, is a good indicator of age, especially when wondering how old an adult is exactly. In an article entitled, “Age and Sex-Related Variation in Hyoid Bone Morphology,” Kevin Miller et al. discuss the diminutive yet important bone. “Researchers have suggested, based on smaller samples, that complete fusion of the hyoid is rare until the third or fourth decades of life.” (Miller et al. 1141) This means that even after most other bones become fairly mute due to fusion, the hyoid bone can still assist archaeologists in determining the more precise ages of adult skeletons.

Another osteologcal method for determining the age of a skeleton can be found in the dentition; the teeth. Similar to bone size, the lay person may think that the only way to age a tooth is to identify it as either a deciduous (baby) tooth, or a permanent (adult) tooth. And also similar to bone size, this is not the case. It is true however, that a skeleton with deciduous teeth would in all likelihood belong to a sub-adult, since it is a universal biological process that all of the permanent teeth (with the exception of the third molars in some cases) erupt by the time a person is in their late ‘teens, leaving no remaining deciduous teeth by age twenty.

But once all of the deciduous teeth have been replaced, how would an archaeologist be able to age an individual? The solution to this problem can be solved by studying tooth-wear. Tooth-wear and advanced age have an especially close correlation in pre-historic populations, due to the un-refined food they consumed. In an article titled “Estimating Age from Tooth Wear in Archaeological Populations,” Phillip Walker et al. reinforce this point.

“Dental attrition is also an important source of data on the age structure of prehistoric populations. The demographic information provided by tooth wear varies according to the abrasiveness of the diet. Most prehistoric people consumed tough, grit-contaminated foods. This caused rapid tooth wear and produced a strong correlation between chronological age and severity of attrition.” (Walker et al. 169)

Walker then goes on to explain how to measure dental attrition. First, a “wear standard” must be established. Walker discusses the standard. “Developing a wear standard for use in aging archaeological remains is a three-stage process. First, the ages of a sample of burials must be determined using an age indicator with a known relationship to chronological age that is independent of tooth wear.

“Next, the tooth wear of these independently aged individuals is recorded. Lastly, the relationship between the independent age indicator and wear is analyzed to determine a population specific wear rate. This wear rate can then be used to age people solely on the basis of the severity of their dental attrition.” (Walker et al. 169-70) However, even if one had not established a wear standard, the relative ages of individuals at a site could be reasonably estimated from the degrees of dental attrition.

A slightly different approach is used in another article relating age to dentition. The article was first presented at “The VI European Meeting of the Paleopathology Association,” and it is titled “Correlations Between Age of Death and Tooth Size.” The article is written by A. Perez – Perez, and the frequently cited Phillip Walker. This article states that “Studies of prehistoric human populations have demonstrated that the dental dimensions of people who die early in life tend to have smaller teeth than those of people who die later in life.” (Perez, 261) Perez defends this position by saying “The age – related differences in tooth size are a phenotypic response to unfavorable environmental conditions during dental development. There is evidence that dental dimensions are influenced by environmental factors such as exposure to infectious diseases and malnutrition. Exposure to stressors such as these could lead to stunted dental development as well as early death.” (Perez, 261-2) This is a more difficult age determinant, but still another way of aging skeletal material.

Human dentition can do more for archaeologists than determine the age of a skeleton. Just as a dentist can look into the mouth of a modern person and speculate on the quality of diet they have, so can an archaeologist speculate about prehistoric and historic diets as well. The teeth of a skeleton can tell an archaeologist more about an individual’s diet than their tongue ever could.

As discussed previously, dental attrition is indicative of a gritty, rough diet. But other aspects of dental wear lend insights into other aspects of diet. In historic populations caries, or “cavities” on the teeth show that the individual had a poor quality diet. A case study from 1986, first published in American Antiquity magazine discusses the dental-diet relationship. The article is titled “Dental Evidence for Prehistoric Dietary Change on the Northern Channel Islands, California.” The article focuses primarily on caries and carious lesions. The following section deals with evidence of carbohydrate consumption in dentition.

“Although faunal remains are an important source of information on the amount of protein in a diet, they provide little data on carbohydrate consumption…Dental caries rates, in contrast, can provide an index of the ratio of proteins to carbohydrates in the diet. Clinical and experimental evidence unequivocally links high caries rates to high carbohydrate intake. High protein and fat diets on the other hand, are generally associated with very low caries rates.” (Walker et al. 375-6) Therefore, one can make assumptions about the diet of a population based on the number of carious lesions in the population’s dentition. The caries rate could also help to vaguely date the site, because caries are rarely seen in prehistoric sites. “Paleopathologic studies show that caries rates are relatively low among hunter – gatherers whose diets contain substantial quantities of animal protein, but increase markedly when these same populations adopt a carbohydrate-rich diet based on cultigens.” (Walker et al. 376)

Caries, and other infections as well as injuries that are visible on the bones at archaeological sites are known as pathologies. The study of pathologies is one of the many invaluable sub-methodologies in osteology. Archaeologists can learn volumes of information from skeletal pathology. What diseases were present in a population, whether violence was present in a population, and as mentioned earlier, what diet was present in a population, all of these secrets can be uncovered, if one can unlock the bones.

One of the main reasons to study pathology is to determine the cause of death for individuals being studied. The question usually is whether the death was natural or violent. It is sometimes difficult to figure out whether the pathology is peri-mortem (cause of death) or post-mortem (after death), but the answer can be found. An interesting article regarding this matter was published in the American Journal of Physical Anthropology by Phillip Walker. It is entitled “Cranial Injuries as Evidence of Violence in Prehistoric California.” The article refutes the historical view of the Chumash Indians of California as non-violent, with pathological evidence to suggest frequent violence in reality.

Walker uses the following criteria to determine a cranial injury caused by intentional trauma. “An absence of reactive bone indicative of infectious etiology, a tendency for the injuries to be a single and a lack of lesions elsewhere in the skeleton suggestive of a systemic infection, the well-delineated circular or ellipsoidal shape of many of the lesions, and the retention in some cases of fracture lines at the periphery of the depressed area.” (Walker, 315) In other words, Walker needed to make sure that the pathologies actually did come from blunt-force trauma, and not from some other cause, such as infectious diseases. Studying pathology can help an archaeologist to recognize these differences, to correctly identify the cause of death in individuals.

But aside from trauma, pathology can also be used to gather information about diseases in a population. Walker also published an article regarding this matter titled “Anemia Among Prehistoric Indians of the American Southwest.” The article talks about the skeletal evidence of anemia in a population. Walker writes, “A number of osseous (skeletal) changes occur as part of the body’s response to anemia. The most obvious of these is the development of areas of porous, often sponge-like bone on the external surface of the cranium known as porotic hyperostosis.” (Walker, 139) Walker’s skulls displayed characteristics of anemia, helping him to diagnose the pathology properly.

However osteology can teach the researcher more about individual than just the cause of death, but their way of life as well. When a body is under mechanical stress, it develops more muscle mass to accommodate the more rigorous life-style. These large muscles then form rugged “tubercles” or attachment surfaces on the bones they are joined to. The larger and more rough the tubercles on a bone, the more muscle an individual must have had, which means that individual, and probably a population was under an unusual amount of mechanical stresses. However, if a population is under too much stress, then they can experience trauma, such as bone lesions and torn muscles. Walker writes about this in an article called “Skeletal Evidence for Stress During a Period of Cultural Change in Prehistoric California.” He writes about bone lesions being indicative of mechanical stresses. “Inflammatory bone lesions have been associated with infectious disease, nutritional deficiencies and trauma.” (Walker, 208) With a knowledge of pathology, Walker was able to determine the number and type of stresses on a population.

Osteology as a discipline is broad and over-arching, but within it there are enough sub-disciplines to arm an archaeologist to the teeth with methodologies for gaining information about a population. Everything from what a population does, to what they eat, to how they kill each other can be discovered if an archaeologist were to study the osteological record of a site. Human osteology is an invaluable methodology for all archaeologists, no bones about it.