Think that Flipper is all cute and cuddly? Australian researchers have discovered the dark side of dolphin social structure:
The male dolphins of Shark Bay, Australia, are known to marine biologists for their messy social entanglements. Their relationships with each other are so unusual—they're more like the intricate webs of the Mafia than the vertical hierarchies of chimpanzees—that, in a new paper, one team of scientists argues that the dolphins live in a social system that is "unique among mammals."
At first glance, dolphins seem to have a somewhat similar social system [to chimpanzees']. Two or three adult males form a tight alliance and cooperate to herd a female for mating. (Female dolphins rarely form strong alliances.) Other male teams may try to spirit away the female—particularly if she is in estrus. To fight back, the first-level alliances form partnerships with other first-level alliances, thus creating a larger second-level alliance. Some of these second-level alliances have as many as 14 dolphins and can last 15 years or more. On some occasions, the second-level alliance can call in the troops from yet another group, "a third-order alliance," as the researchers call them—leading to huge battles with more than 20 dolphins biting and bashing each other with their heads and tails over the right to keep or steal a single female.