Scientists say that there are 45 different species of dolphins, five of which are river dolphins. Bottlenose dolphins live up to 40 years while the Orca (killer whales) can live up to 80 years. Dolphins sometimes die when they become trapped in fishermen’s nets. Dolphins live in groups called schools or pods. A female dolphin leads the herd.

Dolphins are small-toothed cetaceans easily recognizable by their curved mouths, which give them a permanent “smile.” There are 36 dolphin species, found in every ocean. Most dolphins are marine and live in the ocean or brackish waters along coastlines.

Most dolphins give birth to one (sometimes two) babies about every three years. The dolphin baby, which is born after a 12-month gestation period, is called a calf. Female dolphins are cows and males are bulls. The calf drinks its mother's milk for up to 18 months. Sometimes another dolphin stays nearby to help with the birth.