The dolphin is a marine mammal within the order Cetacea. There are 40 extant species of dolphin. Dolphins, alongside other cetaceans, belong to the order Cetartiodactyla, with even-toed ungulates. Their closest living relatives are the hippopotamuses, having diverged about 40 million years ago.

The bottlenose dolphin, like the sketch here, inhabits warm waters worldwide. They travel in pods, groups of 10-30 members. They have the second largest brain to body mass ratio of any mammal on Earth after humans, which more than likely attributes to their incredibly high intelligence and emotional intelligence.