I have no doubt that once we've self-exterminated (probably by nuclear war within the next 50 years) that life on Earth will recover and new species will come into existence just as they always have done. It's extremely unlikely that any other species will develop the kinds of tools we've created, so life on Earth will return to more basic modes of change. As this is almost certainly one of the very rare celestial bodies on which eukaryotic life arises, our self-extinction is greatly to be desired. If we cling on too long, we may end up doing even greater harm to all the other life on this precious little planet. That said, if life can survive the various historical extinction events - some of which being far worse than anything we can engineer - no doubt life will adapt regardless of what we foolish apes manage to do in the brief time remaining to us.