Dolphins are very intelligent creatures marine biologists think they could be smarter than primates! they can learn tricks very easily, and communicate using a variety of clicks and whistles. Dolphins are mammals but do live in water they come up to breath through a blowhole on the top of its head. Also dolphins can not sleep or else they would drown. So they let half of there brain fall asleep and sleep about 8 hours a day. Dolphins can sleep 3 different ways swimming very slowly and coming up to breath now and again. Resting at the surface with there blowhole exposed, or resting on the bottom of shallow waters and coming up to breath every once in a while. There are 32 species of oceanic dolphins and about 5 river species. An average bottlenose dolphin can live between 40-50 years. Most dolphins can dive up to 300 meters (990 ft) and stay under for around 2 minutes but can be trained to stay under for 7 min. Dolphins can grow to around 3ft long and eat 50 lb of food per day. Most dolphins travel in groups called pods were up to 1,000 dolphins can live together. A dolphins skin sheds constantly so algae can't grow on it.
