In the great upheaval of scientific thought that followed the announcement of the theory of evolution ... materials upon which they depend are the mutations of genes. The hereditary endowment ...

under continued input of new mutations" (Kimura, 1991) Immediately, this theory caused controversy and gave rise to opposition from many evolutionary biologists. However, the theory also made ...

Tiny genetic alterations could help the bird flu virus enter cells in the upper respiratory tract, the C.D.C. said. But there ...

How could a "bad" gene-- the mutation that causes the sometimes lethal sickle cell disease -- also be beneficial? On the other hand, if it didn't provide some survival advantage, why had the ...

Charles Darwin's theory of evolution generated scientific ... Still others proposed that spontaneous, random mutations, or changes, in organisms accounted for the variety of species.

Variation is the differences in the characteristics of organisms. It can be caused by the genes an individual inherits or the environment it lives in. Extensive genetic variation is contained ...