How Do Spiders Legs Break?
WouterMany spiders use a leg or two for a number of purposes. They may be able to use a leg to escape a predator, to straighten out their legs or for building a web. In addition, some spiders have venom in their fangs and they may use their limbs as a defense.
One of the most remarkable spider defenses is autotomy. A male spider folds his legs against a female’s body, and catapults himself. It is possible that this defense is a strategy to distract her.
Another amazing spider defense is the ability of spiders to regenerate their legs. Spiders often regenerate their legs when they are young. Regeneration of legs reduces the resources required for survival.
The most common type of regeneration is a hydraulically driven extension of the legs. Researchers have shown that spiders can extend their legs by releasing hydraulic pressure from their abdomens. This hydraulic extension is similar to previous findings in jumping spiders.
An alternative method is to dampen the antagonistic muscles. This prevents ringing, a premature interruption of the jumping sequence. However, this method has the disadvantage of reducing the power of the extension.
When spiders regenerate their legs, they have a smaller exoskeleton than the original legs. This means that they will not be able to stand up as high as if they had their original legs. That may be a disadvantage in the wild.
Researchers also have the option of removing one or both of their front legs. Male spiders do this to gain advantage in a mating situation. Their ability to do so does not affect their ability to mount a female.
