Foundations of Behavior Genetics

For evolution by natural selection to work, hereditary material must vary between individuals and such variation must cause individual differences in traits that are directly, or indirectly, involved with reproductive fitness. In other words, genetic differences between individuals are the raw material of evolution, but only if those differences produce differences in traits that are subject to natural selection. Theodosius Dobzhansky’s assertion that biology only makes sense in the context of evolution makes it clear that genetic variation is a cornerstone of the entire field of biology. It is certainly the basis of behavior genetics, where we strive to understand the role of genetic differences in producing individual differences in behavior.