[GluteusMax]

Are the creatures at one end of the daisy chain 'ring species?' How about the other end? The fact they don't do the wild thing with those farther away doesn't change the fact they are still members of the same species.

It's akin to saying that canaries with wildly different beaks are somehow a different species. Or that Iguanas that have adapted to their new marine environment are a different species.

That all easily falls within changes accomodated by the robustness of the design.

Now if someone could produce some transitional thing between an amphibian and a reptile that would be something. (A common "truth" taught when I was a lad.)

Of course that's impossible. Every pitiful attempt at a partial evolving transitional creature would result in a dead thing from birth.

[Doctor Stochastic]

Are you saying that two groups of organisms that cannot interbreed are still of the same species? If so, what is your criteria for species?

[Junior]

In at least one instance of a ring species, the two ends butt up against one-another -- and cannot mate successfully, though each end can mate with the subspecies on the other side all the way around.

[dangus]

>> The fact they don't do the wild thing with those farther away doesn't change the fact they are still members of the same species.>>

Actually, biologists DO refer to "geographic speciation."