bottlenose dolphins are crowd favorites. they're not fish. they're mammals.he babies get milk from their mothers, and just like us, they're sociable. and how smart are dolphins? >> dolin it's kind of hard to categorize exactly how smart they are because there's no true way of knowing, but they're very socially complex animals. they learn pretty easily. so, it's a lot of fun to work with them. >> i was soon going to find out just how true that is. but one more question first. and how do they communicate with each other? >> they communicate in a lot of different ways. so, most of the time, when people think of dolphins and communication, they think of vocalizations, like clicks and whistles. and that is part of it. we don't know, obviously, what they're saying. that's between them. but the other ways they communicate, sometimes, is body language. so, a lot of times, they will jump out of the water, make really big splashes. they'll kind of hit their pectoral or flukes against the surface of the water, and that's all communication among the dolphins. >> dolphins