Dolphins are a widely distributed and diverse group of fully aquatic marine mammals. There are 40 extant species of dolphins. Their closest living relatives are the hippopotamuses, having diverged about 40 million years ago. Dolphins range in size from the 1.7-metre-long (5.6 ft) long and 50 kg (110 lb). There are 40 extant species of dolphins.
Technical DetailsIssue Date: 17.11.2016
Values: MVR 60