Nature
Millions of ant nests along 6,000km of coastline treat each other as one colony
In their native South America, Argentine ant colonies are small and viciously territorial. But researchers sampling ants across the Mediterranean and Atlantic coasts of southern Europe found nests spanning roughly 6,000 kilometres that don't fight each other at all — workers from opposite ends of the supercolony treat one another as nestmates. It was described as the largest cooperative unit ever recorded in an animal species.