Like some “B-grade” horror movie, a giant colony of Argentine ants stretching 60 miles has been discovered in the Australian city of Melbourne, threatening the local insect population.

Argentine ants may look like any ordinary household ant, but they are aggressive and are regarded as one of the world’s 100 worst animal invaders, displacing native plants and animals, according to Monash University scientist Elissa Suhr.

“In Argentina ant colonies…are highly aggressive toward one another,” said Suhr, who has studied the giant Argentine ant colony.

“Population numbers (in Argentina) never explode and they are no threat to other plants and animals,” Suhr said in a statement received on Thursday.

“In Melbourne, their genetic make-up and behavior is really different. Here, Argentine ants no longer fight and have formed a supercolony extending at least 100 kilometers across the city.”

Argentine ants have been discovered across Australia.

Suhr said the ants had genetically changed during their voyage from Argentina and that had in turn changed their behavior, which now threatened local plants and insects.

More here.