Whenever evolution is the title, darwins theory comes into mind... When we see our ancestors,we hardly resembles with them physucally... Natural selection is much more evident , there were early man period, before that ,those were all together different from homosapiens....
As you mentioned"Eventually so much change will have occurred that the species will be unrecognizable compared to its distant ancestors. Creationists argue that this can't happen; that some unspecified force will stop canines, for example, from changing so much that they are no longer recognizably canine."