Why Do Spiders Turn Over When They Die?
WouterSpiders play dead for a few minutes to several hours after they die. They do this as a protective tactic, a mating ritual, or simply to ward off potential predators. This tactic is also used by snakes, birds, and even humans. The problem with playing dead is that it can be dangerous.
When a spider dies, its legs curl up. This is called tonic immobility. Tonic immobility is a defense tactic that is usually used as a last resort.
Scientists are now trying to use the spider’s hydraulic system to design a robot that has spider-like joints. Researchers at the Rice University have already created a wolf spider robot that can pick up and hold objects. Eventually, a robot that can replicate spider movements and functions will be able to invade the world of the small.
In addition to the spider’s hydraulic system, the spider’s legs are equipped with flexor muscles. These muscles are used to retract and extend the legs. When the spider is alive, these muscles help the spider climb walls. When it dies, the flexor muscles release and revert back to their original length.
When the spider’s flexor muscles relax, the spider releases hemolymph, which is the spider’s equivalent of blood. The pressure from the hemolymph causes the spider’s legs to contract. However, when the spider dies, the flexor muscles are no longer able to maintain tension on the leg, which makes the spider’s legs fall to the ground.
