STEVE INSKEEP, HOST:
Good morning. I'm Steve Inskeep. People know of dolphins as friendly and sociable. But we don't often hear the dolphin gangs. A new article in Science magazine says gangs are part of dolphin culture. Male dolphins band together to fight off rivals and capture females in heat. They learn the signature whistles of fellow members. Science magazine writes, quote, "like members of a street gang, male dolphins summon their buddies when it comes time to raid and pillage." It's MORNING EDITION. Transcript provided by NPR, Copyright NPR.