Creationism and Ignorance

[FatAndFaithless]

So, changes in allele frequency over time as driven by natural selection?  Phenotypic differences and heritable traits are driven by alleles.

Yeah, it helps to clarify that it isn't through any action taken by an individual organism which changes his own morphology, but just the advantage to the future generations of the lucky individual with the positive natural mutation whose offspring will inherit the that random change.

How about "Changes in allele frequencies in populations over time, as directed by natural selection."  That's still a pretty concise, neat sentence.