Argentine ants living in vast numbers across Europe, the US and Japan belong to the same inter-related colony, and will refuse to fight one another.
The colony may be the largest of its type ever known for any insect species, and could rival humans in the scale of its world domination.
What's more, people are unwittingly helping the mega-colony stick together.
Argentine ants (Linepithema humile) were once native to South America. But people have unintentionally introduced the ants to all continents except Antarctica.
