Evolution is quicker than they thought

[piercehawkeye45]

Originally Posted by rkzenrage

Of course species mutate in response to situations... that's the idea.

No, what happens is there is already genetic diversity and natural selection will take its course (assuming we leave out the four other variables for microevolution).

For viruses for example, lets assume that there are four different types of virus A: AA, AB, AC, and AD. Lets say there are 1,000 virus strains and 950 are AA, 20 are AB, 20 are AC, and 10 are AD. When we add an antibody to kill the virus, we find out that the type AB is already immune to the antibody. So after we add the antibody, the number of virus strains go down from 1,000 of 4 different kinds to 20 just AB making it seem like the virus is gone but then the AB virus will grow again and in a week or so we will have 950 AB viruses, 20 AA, 20, AE, and 10 AF. We add the antibody again but since AB is immune to it, 950 virus strains will remain and it will seem that the virus has mutated in response to the antibody when in reality, the conditions changed and the virus strains that were already immune to the antibody were the only ones that survived (microevolution).

Mutations are random, natural section is not.