Wednesday, November 13. 2019
Playing dead is a survival strategy performed by hundreds of different species, including lemurs, lizards, ants and sharks. But why do animals do this? This bizarre behaviour, know as tonic immobility (TI) or catatonia can be used as a defence or offence.
Since most predators avoid dead or rotting animals displaying catatonia is usually enough to keep predators from killing and eating them. An opossum for example, assumes an odd body posture, sticks out its tongue, drools and oozes a foul smelling liquid from its anal gland. Disgusted, the predator usually decides it’s not the meal it was looking for and leaves. After a few minutes the opossum jumps up and heads on its way.
Animals also play dead in order to catch prey. There is a species of beetle that pretends to be dead and is carried away by ants to their ant nest. Once inside, the beetle springs back to life and feeds on the ant larvae.
Another form of immobility is called clipnosis. A mother cat will pick up their babies by pinching the napes of their neck with their teeth, causing them to hang lifeless and quiet. This induced behaviour avoids attracting unwanted attention from predators when transporting them from one den site to another.
Humans can also experience tonic immobility when they freeze when confronted by a potentially violent attack. An example of this would be if a grizzly bear was to rush towards you unexpectedly invoking this involuntary form of self defence. This counter intuitive behaviour of not fleeing or fighting is not totally understood.
The animal kingdom has so much to teach us, I cannot wait!
By Brad Gates, B.Sc.
Brad Gates is the owner and president of AAA Gates Wildlife Control. He has over 35 years experience in the humane wildlife removal and prevention industry.