The Evolution of Life

When did mutations come into it? In and around the turn of the 20th century or so, people started to look at that after Gregor Mendel and his pee garden in Austria talked about how it started genetics. They would say things like, well, if you were a deer and the weather turned colder and a baby deer was born with longer fur, why, that would be better. So they were thinking in terms of improving body features.