This is a species of Australian ant. It has an interesting colony-scale ability to evade threats. It’s a behavior that researchers believe is a recorded world first. These are the ants that play dead. All at the same time.
It was discovered accidentally. Researchers were checking nests of pygmy possums and bats on Kangaroo Island. A colony of Polyrhachis femorata ants appeared to be dead… until one moved. It was a defensive strategy to avoid potential danger.
Dead and then not
It was published through CSIRO – the Australian research agency. This is the first time a whole colony of ants has been recorded pretending to be dead. And it is the first record of the ant species Polyrhachis femorata for southern Australia.
‘Topa’ Petit is a wildlife ecologist, and associate professor at the University of South Australia. She says she was surprised to discover ants playing dead. “The mimicry was perfect,” Petit says in a statement. “When we opened the box, we saw all these dead ants. And then one moved a little bit.
“This type of defensive immobility is known only among a few species of ants. Only in individuals or in specific molds. We know of no other cases in which it has been observed in entire colonies.
“In some of the boxes containing colonies of Polyrhachis femorata, some individuals took some time to stop moving. Others did not stop. The triggers for the behavior are difficult to understand.”
Defensive behaviors
This is an opportunity to study the death-simulation behaviors of ants. They are of great interest to many behavioral ecologists. They investigate a diversity of animal species.
The discovery was made during the Kangaroo Island Nest Box Project. They monitored 901 box cavities on 13 diverse properties. It is part of wildlife recovery efforts following the devastating wildfires of 2020.
