“Playing possum” describes feigning unconsciousness, an idiom originating from the North American opossum’s defense mechanism. Many wonder if these marsupials genuinely faint or consciously deceive predators. This article explores the science behind the opossum’s unique reaction to danger, a complex biological response that aids its survival.
The “Playing Possum” Phenomenon
Opossums do not truly faint, which involves a loss of consciousness from reduced blood flow to the brain. Instead, they exhibit tonic immobility or thanatosis, an involuntary physiological state. This automatic reaction, a catatonic state, is triggered by extreme fear or stress.
When threatened, an opossum’s body goes limp, often falling onto its side with its mouth open and tongue lolling out. Its muscles become rigid, and it may appear unresponsive to touch. Breathing becomes shallow and irregular, and heart rate can decrease significantly, by as much as 46%. Body temperature may also drop slightly, around 0.6°C. To enhance the illusion of death, the opossum may drool, urinate, defecate, and secrete a foul-smelling fluid from its anal glands. Despite these physical manifestations, the opossum remains fully conscious and aware of its surroundings.
Why Possums Play Dead
Playing dead serves as an effective defense against predators like bobcats, coyotes, foxes, and owls. Many predators prefer live prey, losing interest in an animal that appears deceased. The opossum’s foul odor, mimicking decomposition, further enhances the illusion and deters attackers who avoid carrion due to disease risk.
This involuntary reaction is a last-resort strategy, typically employed when an opossum is cornered and cannot escape. It is a deep-seated instinct, a neurochemical response involving hormones and neurotransmitters that shut down voluntary motor functions. This survival tactic increases the opossum’s chances of survival by making it seem unappealing or dead to a predator. While feigning death occurs in other animals, opossums are particularly well-known for their convincing display.
Encountering a “Playing Possum”
If you encounter an opossum exhibiting tonic immobility, leave it undisturbed. The animal will remain in this catatonic state for varying periods, from a few minutes to several hours, until the threat passes. Attempting to approach or touch it, even if it appears lifeless, can prolong its stress or provoke a defensive reaction. While generally non-aggressive, an opossum might bite or scratch if directly threatened.
Keep pets away from the opossum to allow it to recover safely. Observe the animal from a distance. Once it perceives the danger is gone, the opossum will gradually recover and move away on its own. If the opossum appears injured or is in an unsafe location like a road, contact local animal control or a wildlife rescue organization rather than attempting to handle it yourself.