Delfiny to niezwykle inteligentne mammals należące do grupy waleni. They eat fish, and some species of dolphins with other marine mammals. They have perfectly developed hearing and sense of smell. They communicate through the sounds they make and rubbing. They live in groups, they take care of their offspring together, zaprzyjaźniają się z człowiekiem, they often save drowning people. The largest dolphins can be 10 meters long.