Human traits like hair distribution, fatness and fat distribution, blood chemistry, and ear form are known to be affected by variation in dozens or hundreds of genes. (medium.com)
Tanner staging relates to the development of genitalia and pubic hair distribution and how it relates to usual progression from childhood to adulthood. (tctmed.com)
The problem is to find categories that are genuinely illuminating, in the sense that they provide a rational basis for understanding what people are and why they behave as they do.One of the ways of classifying people is by inheritable physical characteristics, such as size and shape of head, physiognomy, hair distribution and type, skeletal structure, body proportions, blood type, and skin and eye pigmentation. (religion-online.org)