ANTH-101 Study Guide - Quiz Guide: Heredity
Document Summary
Conventional geographic racial groupings differ from one another only in about 6% of their genes. This means that there is greater variation within racial groups than between them. In neighboring populations there is much overlapping of genes and their phenotypic (physical) expressions. Physical variations in any given trait tend to occur gradually rather than abruptly over geographic areas. And because physical traits are inherited independently of one another, knowing the range of one trait does not predict the presence of others. For example, skin color varies largely from light in the temperate areas in the north to dark in the tropical areas in the south; its intensity is not related to nose shape or hair texture. Historical research has shown that the idea of race has always carried more meanings than mere physical differences; indeed, physical variations in the human species have no meaning except the social ones that humans put on them.
