Actually:
genetic drift - any change in gene frequency due to a change in population.
Thus, if all redheaded woodpeckers are eaten by a redheaded woodpecker predator, only the non-redheaded woodpeckers will survive. Redheaded woodpeckers will cease to exist as long as the predator survives to eat them. This is NOT a mutation of genes.
You are quite right, Scully. After I posted the "=" sign I realized that someone might read this out of context and call me on it.
Let me provide the context for you:
Nakatu X: However, the incredible number of mutations it takes to go from bacteria to human being is incredible.RA: But its not just mutations. Do not forget genetic drift.
In this context, genetic drift is not separate from mutations. That is, genetic drift provides direction but does change number of mutations it took to get from bacteria to human beings.
To RadioAstronomer's credit, he may have been indicating that mutations are not a wild random ride from bacteria to humans and that genetic drift, along with natural selection, and along with a multitude of other processes ensure a shorter parthlength between the two.
Thank you for clarifying. (RadioAstronomer, BTW, posted a handy link at #57.)