The secret of Australian ants to defend themselves: the entire colony plays dead

By 11/05/2023 Portal

The trick of 'playing dead' is common in nature: guinea pigs and many species of rabbits pretend to have perished, as well as various types of snakes or even some sharks. Without a doubt, the one that best plays the role of deceased is the North American opossum, which opens its mouth, sticks out its tongue, empties its intestines and secretes malodorous fluids. Now, Australian researchers add a new family to the list: the Polyrhachis femorata ants, who not only simulate their death, but all members of the colony do so at the same time. The results have just been published in the 'Australian Journal of Zoology'. Accidentally discovered while researchers were checking nests of pygmy possums and bats on Kangaroo Island (off the coast of South Australia, southwest of Adelaide), the ant colony appeared to be dead... until one moved. "The mimicry was perfect," explains Sophie 'Topa' Petit, professor of Ecology at the University of South Australia, in a statement. "When we opened the nest box, we saw all these dead ants... and then one moved a little bit." The researchers believe the ants were 'playing dead' as a defensive strategy to avoid potential danger. "This type of defensive immobility is known only among a few species of ants, but we know of no other cases in which it has been observed in entire colonies." Upon closer inspection, they observed that it was not completely perfect behavior: some individuals took longer to freeze and some others did not stop their activity. "Behavioral triggers are difficult to understand," Petit points out. MORE INFORMATION news No The secrets revealed by the DNA of the mummy of the ill-fated Infanta Leonor of Castilla news No The pangenome, humanity's most precise 'recipe', in some keys The researcher points out that these anthills, which were installed as an effort to recover wildlife after the devastating wildfires of 2020, may present a great opportunity to study this curious behavior. "Polyrhachis femorata is a beautiful arboreal ant that tends to be quite shy, but little else is known about its ecology or behavior," says Petit. We have a relatively unknown world of ants under our feet and in the trees. "Ants provide crucial ecosystem services and are a vital part of the functional ecosystems on Kangaroo Island."