Dolphins are social

Dolphins are often regarded as one of Earth's most intelligent animals, though it is hard to say just how intelligent. Comparing species' relative intelligence is complicated by differences in sensory apparatus, response modes, and nature of cognition. Furthermore, the difficulty and expense of experimental work with large aquatic animals has so far prevented some tests and limited sample size and rigor in others. Compared to many other species, however, dolphin behavior has been studied extensively, both in captivity and in the wild. See cetacean intelligence for more details.
Social behavior


Dolphins surfing at Snapper Rocks, Queensland, Australia
Dolphins are social, living in pods of up to a dozen individuals. In places with a high abundance of food, pods can merge temporarily, forming a superpod; such groupings may exceed 1,000 dolphins. Individual dolphins communicate using a variety of clicks, whistle-like sounds and other vocalizations. Membership in pods is not rigid; interchange is common. Dolphins can, however, establish strong social bonds; they will stay with injured or ill individuals, even helping them to breathe by bringing them to the surface if needed.[38] This altruism does not appear to be limited to their own species. The dolphin Moko in New Zealand has been observed guiding a female Pygmy Sperm Whale together with her calf out of shallow water where they had stranded several times.[39] They have also been seen protecting swimmers from sharks by swimming circles around the swimmers[40][41] or charging the sharks to make them go away.