William Lane Craig continues to desperately defend the indefensible.

[Esquilax]

The theory of evolution assumes just that. Change over time. You are willing to accept that animals evolve new traits over a short period of time. So why put an arbitrary limit on how far animals can evolve over a much longer period of time?

And it really is arbitrary: the species definition isn't an objective feature of biology, it's a label invented by humans to better categorize living things. All that's really happening is the real world is proving to be wider than human definitions, and that happens all the time.