The cultural brain hypothesis of human development could also explain cetaceans forming friendships and even gossiping
Life is not so different beneath the ocean waves. Bottlenose dolphins use simple tools, orcas call each other by name, and sperm whales talk in local dialects. Many cetaceans live in tight-knit groups and spend a good deal of time at play.
That much scientists know. But in a new study, researchers compiled a list of the rich behaviours spotted in 90 different species of dolphins, whales and porpoises, and found that the bigger the species brain, the more complex indeed, the more human-like their lives are likely to be.
This suggests that the cultural brain hypothesis the theory that suggests our intelligence developed as a way of coping with large and complex social groups may apply to whales and dolphins, as well as humans.
Writing in the journal, Nature Ecology and Evolution, the researchers claim that complex social and cultural characteristics, such as hunting together, developing regional dialects and learning from observation, are linked to the expansion of the animals brains a process known as encephalisation.
The researchers gathered records of dolphins playing with humpback whales, helping fishermen with their catches, and even producing signature whistles for dolphins that are absent suggesting the animals may even gossip.
Another common behaviour was adult animals raising unrelated young. There is the saying that it takes a village to raise a child [and that] seems to be true for both whales and humans, said Michael Muthukrishna, an economic psychologist and co-author on the study at the London School of Economics.