Curious question regarding evolution though: what would be the ethics of keeping early hominoids in zoos? When did our ancestors become too human to keep in zoos?
Ha ha, I've wondered the same thing. At the very least, I don't think modern zoos would go for anything that can truly speak, communicate with humans without much difficulty, though I imagine we would draw the line a little earlier. While we're at it, I wonder if environmental protection laws would be different for them?
Actually wasn't there some ancient type of pygmy hippo from Cyprus or Malta or one of the islands in the Med? They might be nice in zoos.
The modern pygmy hippo seems to do well in zoos, I'm sure the Mediterranean species would have done fine.
Speaking of hippos, I bet the European hippo would, at least, be common in European zoos.