>>81693439I think reptiles are in the same situations as mammals. Birds are a mystery, but I vaguely recall hearing some birds chirping, so they might not have evolved like mammals did. Fish and insects definitely aren't sapient, and for that matter, I doubt crustaceans and other invertebrates are either.
Oceanic mammals are the biggest mystery. Given that there's simply no way for sea animals to build any sort of civilization (they don't have hands, for starters), it might be simpler to just keep them as they are. And animals that spend the majority of their lives underwater wouldn't really be able to develop vocal cords that would allow them to converse with land animals either. Also, if you evolve a dolphin too much, at some point, it'll pretty much stop resembling a dolphin. Dolphins are pretty intelligent, but if they're gonna reach the same level as humans, they'd really have to leave the sea at some point.
