In the 19th century, British naturalist Sir John Lubbock conducted a rather unusual experiment to understand how ants recognise members of their own colony.
He placed 50 ants in whisky for a few moments, making them so intoxicated that they could barely move.
He then marked them with tiny spots of paint and placed them near sober ants from one of the colonies.
The sober ants initially seemed confused by their helpless companions. Eventually, they began carrying them away.
But something remarkable happened: ants belonging to their own colony were mostly carried back to the nest, while unfamiliar ants were generally taken to the edge of a water barrier and dropped in.
Out of 25 intoxicated colony members, 20 were carried into the nest, while five were discarded.
Of the 25 strangers, 24 were dropped into the water and only six were initially taken inside, with four subsequently removed.
Lubbock concluded that ants could recognise their colony members even when they were too intoxicated to behave normally.
His experiment, conducted in the 1870s, provided an early insight into the remarkable social recognition abilities of ants.
