There are amazing mammals all over the world, but dolphins are one of the most unique and intelligent. Most species of dolphins live in oceans, but there are some such as the boto dolphin that live only in rivers.

Other dolphins such as the hourglass can live in icy waters that are only 37°F, which is barely above freezing! Dolphins breathe through their lungs but must come to the surface of the water to get the air. They can breathe out and then in again in less than a fifth of a second! Since most mammals have big appetites, dolphins can eat up to twenty pounds of food a day. They mainly eat different kinds of fish and other sea creatures that are of course smaller than them.

Like most mammals, dolphins control their bodies through their nervous system. The brain is the control center, carrying out many functions automatically, but also acting upon information supplied by the senses.

Dolphins have much bigger brains for their size, almost identical to those of humans. They treasure the same five senses we do, though their sense of taste and smell seem very limited.

Hearing is their most important sense. They pick up sounds with their tiny ears that are located just behind their eyes. Species, such as the bottlenose, can be easily trained, has a good memory, and is a superb mimic.

They are also good at solving problems, which is one thing their trainers consider a sign of intelligence. Dolphins use sounds to communicate with one another, and many also use it to locate their food. Scientists have concluded that dolphins are one of the most significant underwater mammals there are on earth.