Sargatanus t1_jcw0maq wrote

Two species that were so closely related that interbreeding was possible, and archaeological evidence suggests that Neanderthals copied the tools and practices of Homo sapiens rather than creating their own, so I don’t think that quite counts, but I digress. If a species of dinosaur or therapsid had built cities and spaceships (which would be cool, but there’s no evidence for that) then that would be a different story.


Sargatanus t1_jcvove9 wrote

I suspect that while we will soon discover that simple, prokaryotic life is common if not abundant, the conditions needed for complex (let alone intelligent) life are quite rare. I have no doubt that there is intelligent life elsewhere in the universe, but I’m skeptical about there being any in our own galaxy, let alone close enough to swing by and visit.

EDIT: It’s also worth pointing out that our definitions of “intelligent” and “life” could be (and likely are) extremely narrow and incomplete. In fact I would say that if we did encounter intelligent life, there’s a good chance that at first we might not even recognize it as being alive, let alone intelligent.