![]() There is no listing out of genes or physical features that is with any degree of confidence going to allow you to identify people with a high degree of certainty because variation in humans is not organized into discrete boxes. If races are biologically meaningful, then in theory we should be able to list out biological traits that distinguish a person in racial group A, from a person in racial group B,” said Leonard. “His work showed that not only is race not the top explanatory area, it was the least explanatory by a long shot. These findings have now been replicated using analyses of human DNA variation. He found that racial categories explained only about 6 percent of human variation. His purpose was to see which levels of explanation were best at describing the variation. Lewontin divided variation into three components: within populations between populations and between races. In 1972, evolutionary biologist Richard Lewontin conducted a study that examined worldwide variation in human blood groups that was used as proxies for genetic diversity before DNA analysis came along. That becomes a much better, and more productive way, to describe human variation than races,” explained Leonard. ![]() “What we tend to find with most of these features is that the variation is continuous rather than categorical. ![]() How does this carry over to human traits? Anthropologists have taken characteristics, such as height, weight, skin color, hair form, eye color, etc., from across the world, and mapped them on a geographic space. For instance, rather than distinctly different temperatures and different locations, the map shows a continuous gradient over a geographic space. When you look at a weather map, you see temperature variation across a broad geographic landscape. Leonard suggests thinking of clines as the biological equivalent of the temperature (thermal) gradient on a daily weather map. The concept of clines helps to explain that races as biological categories are not valid. A cline is a gradation in one or more characteristics within a species, especially between different populations. Rather than race, anthropologists say a more accurate way to distinguish differences in populations of people are clines. “A lot of what we see in the early 20th century discussions about human diversity is not only talking about distinct races, but the social implications of those distinct races - claiming these distinctions were justification for hierarchical ranking of different races.” “Hence, that’s the origin of the race concept,” said Leonard. Until recently, these external differences were thought to prove that people’s underlying genetics and ancestry are also very different. However, in contrast, in terms of our phenotype, meaning how we look externally - height, weight, hair color, eye color - we are a very diverse species.” Relative to other species, we are genetically all very similar. “This is the paradox of the human experience. That’s the way we break up and describe the world,” Leonard said. “Races are an artifact of the human mind’s need to put things into boxes. In fact, in 1950, the United Nations Educational, Scientific and Cultural Organization (UNESCO) issued a statement that all humans belong to the same species, and that “race” is not a biological reality, but a myth. The fact that there is so little genetic diversity among humans has been known for a while, but not widely understood, noted Leonard. ![]() What appears to be huge amounts of variation is masking a low level of genetic diversity,” said Leonard. “In reality then, all the variation of traits we see, in some respect, is literally skin deep. Leonard, PhD, biological anthropologist and professor of anthropology at Northwestern University, told Healthline.Īnthropology and human evolutionary biology prove that not only are all humans of the same type, species, and kind, we are also a species that, in the history of evolution, has recently evolved. “Broadly thinking about what part of the world people’s ancestors might have come from is fine, but to take it to the next step and say that somehow different races are different types of humans is incorrect,” William R. These questions become all the more troubling when you consider how science has proved that humans are biologically the same. The recent spate of white supremacy marches has rekindled many questions as to why such groups and ideologies still exist. ![]()
0 Comments
Leave a Reply. |