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Argentine ant
Argentina
Listen to part of a talk in a biology class. The professor is discussing insect behavior. Today we’re going to continue our discussion of social insects, focusing on the Argentine ant, which, as you might guess, is a species of ant that’s native to Argentina. Well consider what happened to this type of ant after some members of this species moved to California from their original habitat. OK, Well, in Argentine, these Argentine ants behave like most ants species around the world. They fight other ants of the same species if those ants are from some other nest. But the Argentine ants living in Californian behave differently. Ants from different nests form a single large colony. Within this colony there is little aggression among ants from different nests. And when they fight in sex from outside their colony, the Argentine ants can quickly recruit a huge army from their network of nests. This of course gives them advantage over other ant species. So then, why do Argentine ants behave differently in California than they do in Argentine? Well, using genetic testing, researchers found that all the Argentine ants in California, their population must’ve been very small. And all the later generation of Argentine ants there must’ve descended from the same few ancestors. So they’re all closely related. This discovery is important because for most social insects, membership in a colony is based on how closely related they’re genetically.