Why do some animals play dead?

Some animals play dead, a behaviour known as thanatosis, to avoid predators that hunt based on movement or show preference for live prey. For example, opossums “play possum” by becoming limp, drooling, and emitting a foul smell to mimic a decaying carcass, deterring predators. Insects like certain beetles and snakes also adopt this strategy when threatened. This behaviour can confuse or dissuade predators, giving the animal a chance to escape once the threat has passed. Playing dead is an effective survival tactic, particularly in environments where predators may lose interest in non-moving or seemingly inedible prey.