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https://www.youtube.com/watch?v=j_QLzthSkfM&pp=ygUMd2hpcCBpdCBkZXZv

A minimum of hereditary disease, good physical stature and temperment and a robust intellect is a short list of desirable traits.

When breeding, those who bring these traits together will advance...

My understanding of evolution includes the genetic part of things.

An uncomfortable subject for many.