I think the "gradualist Darwinian" answer to these abilities of the guppies and sticklebacks is that they have evolved these strategies by the usual gradual processes. > > > > 2 years for guppies to change and 3 years for sticklebacks is not gradual. > > My point is that the guppies and sticklebacks have evolved the ability, over earlier millennia, to make this quick adaptation.-And my point is that all organisms have had this ability from a very early time, in the first one-celled organisms.