A single mega-colony
of ants has colonised much of the world, scientists have discovered.
living in vast numbers across Europe, the US and Japan belong to
the same inter-related colony, and will refuse to fight one another.
may be the largest of its type ever known for any insect species,
and could rival humans in the scale of its world domination.
people are unwittingly helping the mega-colony stick together.
(Linepithema humile) were once native to South America. But
people have unintentionally introduced the ants to all continents
Argentine ants are renowned for forming large colonies, and for
becoming a significant pest, attacking native animals and crops.
one vast colony of Argentine ants is thought to stretch for 6,000km
(3,700 miles) along the Mediterranean coast, while another in the
US, known as the "Californian large", extends over 900km
(560 miles) along the coast of California. A third huge colony exists
on the west coast of Japan.
are usually highly territorial, those living within each super-colony
are tolerant of one another, even if they live tens or hundreds
of kilometres apart. Each super-colony, however, was thought to
be quite distinct.
But it now
appears that billions of Argentine ants around the world all actually
belong to one single global mega-colony.
in Japan and Spain led by Eiriki Sunamura of the University of Tokyo
found that Argentine ants living in Europe, Japan and California
shared a strikingly similar chemical profile of hydrocarbons on
experiments revealed the true extent of the insects’ global ambition.