Why Do Spiders Wrap Their Prey in Silk?
WouterWhen spiders wrap their prey, they are utilizing silk, a protein fiber spun by spiders. This fiber is one of the strongest materials in the natural world. Spiders use this fiber for several purposes, including wrapping their prey and protecting their eggs.
Silk is used to construct a number of types of spider webs, including knockdown and space webs. Knockdown webs combine a maze of lines above a sheet of silk, which delays the prey long enough for the spider to enswathe and catch it. Space webs, meanwhile, are 3-D webs with a maze of threads.
Silk is also used by spiders to build nests. Some of these nests consist of multiple rows of silk threads that radiate out from the spider’s burrow. Flower spiders, for example, sit on flowers and use vibration to detect prey.
Other spiders use silk to immobilize prey. These methods include the use of venom and silk wrappings. Venom helps spiders kill their prey quickly, while silk wraps prevent the prey from escaping.
Another way spiders immobilize prey is by spitting enzymes onto the prey’s bolus. The spiders’ fangs also inject neurotoxins into the prey, which paralyzes the animal.
Many spiders eat flies, mosquitoes, and other insects. Some spiders also build their own webs. They usually consume moths and other flies.
Some spiders have venom glands, which are like hypodermic needles. Most venoms are harmless to humans. However, some species of venom can be deadly. For instance, brown recluse spider venom can be fatal to very small children.
