Coral snakes have their venom, skunks have their smell, and porcupines have their quills. But then there are those creatures, the artists of the animal world, that depend on fine acting to protect themselves from harm.
The Virginia Opossum is perhaps the best-known proponent of the dramatic approach to self-defense. Although the opossum can and sometimes does bare its teeth and snap at predators and other threats, it most often chooses the thespian route.
First, it collapses on its side and enters a catatonic state, complete with fixed gaze and open-mouthed grin. The opossum's respiration then markedly slows. In addition to this deathlike trance, which in itself can confuse a predator, the opossum uses special effects to make itself even less appealing. It drools; it defecates; it passes gas. As a final embellishment, the opossum secretes a foul-smelling green liquid from its anal glands.
But does the audience notice these subtleties? Usually not. Most likely whatever was interested in the opossum at the outset turned its back and left before the performance reached its climax, which can take anywhere from a few minutes to six hours. When the opossum is finished, it takes a quick look around, then stands up and walks away — a true professional.
Another creature that likes to pretend it's dead is the hognose snake. There are several species of the snake, and they can all look mighty fearsome when first cornered. They flatten out the skin around their head and neck and hiss loudly. The impersonation is so convincing that many people mistake hognose snakes for cobras. But if the ruse doesn't work, the snake will flip over on its back, hang out its tongue, and become motionless.
On a smaller scale, click beetles and ladybugs also act out their deaths. A click beetle will remain still on its back and then suddenly "click" itself upright. A ladybug, meanwhile, will exude a bitter, toxic fluid when pretending it's dead. The behavior is called reflex bleeding.