Scientists have discovered a mega-colony of this invasive insect species that stretches across the globe
Argentine ants from three huge colonies in Europe, America and Japan are actually part of one global super-colony, scientists have revealed.
The aggressive insects were first native to South America but humans have since spread them to the four corners of the globe by mistake. The ants have quickly become nuisance pests and attacked crops and even native animals.
But while they are usually highly territorial, researchers found billions of ants living on three different continents refused to fight each other, according to BBC Earth News.
Instead ants from the vast colonies along the Mediterranean coast, California and the west coast of Japan rubbed antennae when they were introduced to each other as if they were family.
Led by Eiriki Sunamura of the University of Tokyo, the researchers in Japan and Spain found these Argentine ants shared a strikingly similar chemical profile of hydrocarbons on their cuticles.
‘The enormous extent of this population is paralleled only by human society,’ the researchers wrote in the journal Insect Sociaux, in which they reported their findings.
To test their mega-colony theory the team selected wild ants from the three largest colonies as well as smaller colonies in Catalonia and Kobe, Japan.
They matched up the ants in a series of one-on-one tests to see how aggressive individuals from different colonies would be to one another.
Two Argentine ants exchange aphid dew. Colonies of these ants ‘farm’ aphids, keeping them close by as a ready source of sugar
Ants from the smaller super-colonies were always aggressive to one another. So ants from the west coast of Japan fought their rivals from Kobe and ants from the European super-colony didn’t get on with those from the Iberian colony.
But whenever ants from the main European and Californian colonies and those from the largest colony in Japan came into contact, they acted as if they all belonged to the same family, despite living on different continents.
It is likely the mega-colony was created by humans transporting insects around the world, and it continues to thrive as they are still mingling this way.
‘Humans created this great non-aggressive ant population,’ the researchers concluded.
Via Daily Mail