of the careful calculation of competitive edge” of specific individuals. However, some people do try to measusre race by hair texture and skin color but in reality there isn't any way to measure race because it's universal.
Moreover, a clinal distribution is a gradual change in phenotype of allele differecnes over gerography and one hypothesis that exaplain this change from Northern to tropical latitudes is sunlight because it's the best source for individuals to acquire vitamin D. Considering the fact that, Northern latitudes has limited sunlight in the winter cause many individuals to become unhealthy. Therefore, “The best way to understand the genetic differences that we find in human populations is … by distance and it's a continuous change from one group to another. And we can look at this by using the example of skin color. If we were to look only at people in the tropics and the people in Norway, we'd come to the conclusion that as we walk from the tropics to Norway, we would definitely see a continuous change in skin tone.” The concept of concordance is important for those who believe that race is biologically real because it means that simple external differences in biology are associated with the complecated internal
dissimilarities. But, in reality “Most of the human variation is non-concordant” because “Skin or eye color or hair color is not correlated with height or weight and definitely not correlated with more complex traits like intelligence or athletic performance.” Regarding the examination of mtDNA similarity by students in the film “Jamil thought he'd have the fewest mtDNA differences with Gorgeous” and “John thought he'd have fewest differences with Kiril and Noah.” But, in reality, Jmail discovers that he and Kiril were more alike than he and Gorgeous. On the other hand, John finds out that his dissimilarities with Kiril and Jakie were identical. The variation among human beings between any two individual within any local population is 85%.