Lewontin showed that the social category of race explains very little of the genetic diversity among us. Furthermore, recent studies reveal that the variation between any two individuals is very small, on the order of one single nucleotide polymorphism SNP , or single letter change in our DNA, per 1, That means that racial categorization could, at most, relate to 6 percent of the variation found in 1 in 1, SNPs.
Put simply, race fails to explain much. Again, all of these individuals will be remarkably the same: On average, only about 1 out of 1, of their DNA letters will be different. A study by Ning Yu and colleagues places the overall difference more precisely at 0. The researchers further found that people in Africa had less in common with one another than they did with people in Asia or Europe. Homo sapiens evolved in Africa; the groups that migrated out likely did not include all of the genetic variation that built up in Africa.
Genetic variation across Europe and Asia, and the Americas and Australia, is essentially a subset of the genetic variation in Africa. If genetic variation were a set of Russian nesting dolls, all of the other continental dolls pretty much fit into the African doll. Genetic variation is highly correlated to geographic distance. Those osteoporosis doctors might argue that even though socially defined race poorly describes human variation, it still could be a useful classification tool in medicine and other endeavors.
When the rubber of actual practice hits the road, is race a useful way to make approximations about human variation? Sickle cell is a genetic trait: It is the result of an SNP that changes the amino acid sequence of hemoglobin, the protein that carries oxygen in red blood cells. When someone carries two copies of the sickle cell variant, they will have the disease. In the U. Yet scientists have known about the much more complex geographic distribution of sickle cell mutation since the s.
It is almost nonexistent in the Americas, most parts of Europe and Asia — and also in large swaths of Northern and Southern Africa.
Globally, it does not correlate with continents or socially defined races. In one of the most widely cited papers in anthropology, American biological anthropologist Frank Livingstone helped to explain the evolution of sickle cell. He showed that places with a long history of agriculture and endemic malaria have a high prevalence of sickle cell trait a single copy of the allele.
He put this information together with experimental and clinical studies that showed how sickle cell trait helped people resist malaria, and made a compelling case for sickle cell trait being selected for in those areas.
Evolution and geography , not race, explain sickle cell anemia. What about forensic scientists: Are they good at identifying race?
Forensic anthropologists assume these algorithms work. But my analysis of four later tests showed that the correct classification of Native American skulls from other contexts and locations averaged about two incorrect for every correct identification.
The results are no better than a random assignment of race. On top of that, human variation does not stand still. It cannot be done based on biology — not by skin color, bone measurements or genetics. It cannot be done culturally: Race groupings have changed over time and place throughout history. Science If you cannot define groups consistently, then you cannot make scientific generalizations about them.
Wherever one looks, race-as-genetics is bad science. To be clear, what I am saying is that human biogenetic variation is real. When researchers want to discuss genetic ancestry or biological risks experienced by people in certain locations, they can do so without conflating these human groupings with racial categories.
It is hard to convince people of the dangers of thinking race is based on genetic differences. And the further back in time one looks, the more common ancestors we would find.
Chang concludes :. In the final analysis, it is our experiences and our culture, not our DNA, that account for most of our differences. The views expressed are those of the author s and are not necessarily those of Scientific American. Peter G. Prontzos is professor emeritus of political science and interdisciplinary studies at Langara College in Vancouver, Canada. Already a subscriber? Sign in. Thanks for reading Scientific American. Create your free account or Sign in to continue.
See Subscription Options. Discover World-Changing Science. Then there were the horrors of the slaughters in New Zealand and Sri Lanka. These biological processes include combining and recombining inherited genetic material over the generations, which produces offspring and descendants who differ from their parents and ancestors. The environment may favor certain characteristics, producing populations that are on the average taller, or darker, or more rugged than other populations from other geographic areas.
Isolation and inbreeding of some populations may produce differences as well. These natural processes occur in humans as well as other animals and are the source of much study in biology and anthropology. However, even if people in different geographic areas differ, it is impossible to draw sharp lines between racial groups. Characteristics of people change gradually from one geographic area to another; where across Central Asia do European "whites" leave off and Asian "yellows" begin?
Anthropologists see races as temporary, changing phenomena, products of genetic processes and natural selection. The races we see today are different from those of yesterday and will be different tomorrow. Scientific creationists, however, have a simple, Scriptural explanation for human diversity. All people today are descendants of the sons of Noah.
Shem founded the Hebrews; Japheth gave rise to the other Semites, Europeans, and the people of India Indo-Europeans ; and Ham was the father of the rest of humanity the "colored" peoples, as one of the scientific creationist writers puts it. The three brothers and their descendants moved to different parts of the world, where according to the scientific creationists, normal processes producing genetic variation produced the diversity of races and nations we see today.
Both scientific creationists and evolutionists recognize the existence of these processes in producing human variation and agree on their importance. The two groups differ considerably on how these processes can operate, however. Scientific evidence of either visible or invisible characteristics found in our species does not support the scientific creationist view of human variation.
Although Homo sapiens has considerable genetic variation as a species, and each individual has many different genes, it is incomprehensible that differences as great as those seen between small, black, lightly built, kinky-haired Negritos of Melanesia and tall, copper, broad-shouldered, straight-haired Greenland Eskimos could occur in only a few thousand years.
To derive this much diversity in such a short time from only three people -- and these as closely related as brothers -- would require rates of mutation, natural selection, and other processes of evolution so high as to most likely cause the extinction of the population. Historical movements of people have been described for years, far longer than the time claimed to exist after the recession of the Flood waters and the beginning of recorded history. Why are there no records of great changes in human variation during this period that are comparable to those described in scientific creationist literature?
There are no accounts of people changing so rapidly during the past years. The evidence we have from history and archeology suggests the current major racial groups have been around for tens of thousands of years.
The scientific creationist view cannot be reconciled with scientific fact. Anthropologists study religions and world views of peoples in every part of the globe. We do so without declaring any one view "superior," "advanced," "better," or "truer. It is not our function as anthropologists to evaluate whether the scientific creationist view is theologically superior to other religious views, whether Christian or non-Christian.
However, as scientists we have a duty to speak out on the nature of science. Whatever its theological merits or demerits, scientific creationism is not scientifically valid and should not be accepted as an alternate scientific view. The American public needs to be aware of the difference between believing in scientific creationism a theological explanation seeking empirical support and accepting evolution as the best scientific explanation for a wealth of data from all natural sciences.
Eve, R. Harrold The Creationist Movement in Modern America. Boston: Twayne Publishers. Frye, R. Is God a Creationist? NY: Scribners. Make a Donation Today. Give a Gift Membership. More Ways to Give. Member Services FAQs. Legacy Society. Science Champions Society. Give a Gift of Stock. Donor-Advised Funds. Employer Matching Gifts. Facebook Fundraisers. Free Memberships for Graduate Students. Teaching Resources. Misconception of the Month. Coronavirus Resources.
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