Those ants crawling across your picnic table this weekend might be members of a massive, transnational ant mafia, recently reported by researchers in Japan and Spain.

Billions of Argentine ants (Linepithema humile) from North America, Europe and Japan are not only interrelated, but when introduced to foreign cousins they get along like old amigos—an unusual reaction for this otherwise hostile breed—reports the BBC.

The conquering colony is composed of three distinct super-colonies—one in California (560 miles, or 900 kilometers, long), one along the Mediterranean coast (3,700 miles, or 6,000 kilometers, long) and one in Kobe, Japan—that all share similar genetic make-ups, and therefore familiar chemical cues.

“The enormous extent of this population is paralleled only by human society,” the researchers wrote in the paper, published in Insectes Sociaux, a journal about social behavior in insects.

Humans are, of course, the reason for the colony’s breadth. People have been accidentally spreading the invasive ants—originally from South America—around the globe for a century and continue to circulate the mega-colony members. The species now inhabits more than a dozen countries and all six of the livable continents.

Image courtesy of Wikimedia Commons