Spider Web
From Halbeeg, the open encyclopedia · Af-Soomaali
71 languages
A spider web is a structure made from silk, a thin fibre produced by specialized glands in the spider's abdomen. This silk is a liquid protein that hardens and becomes tough when it leaves the body. Spiders use their webs to trap flying insects, create shelter, and lay eggs and store food.
Not all spider species produce large, woven webs. Some use short threads to capture prey, while others are active hunters that rely on silk primarily for shelter and protection. Web structure therefore varies greatly among species.
Silk and its production
Silk is produced from glands located on the underside of the spider's abdomen, in structures called spinnerets. Some spiders have multiple types of silk-producing glands, each producing silk with different properties: one strong and structural, one flexible and elastic, and one fine and sticky for wrapping prey. Spider silk is noted for high tensile strength and the ability to withstand impact without breaking. Much research has been conducted into replacing human-made silk with spider silk.
Types of webs
The most common type is the orb web, which has radial threads extending from the centre and an elastic spiral wrapped around them. Other types include the irregular cobweb, the sheet web stretched over vegetation, and the funnel web within which the spider lurks. Some species use a single elastic thread to snare prey.
How prey capture works
When an insect strikes the web, vibrations in the silk threads alert the spider, which uses touch sensitivity to locate where the prey is trapped. The spider then wraps it in more silk and injects venom and digestive fluid that it later consumes. Most spiders do not walk on their webs, instead moving carefully along non-sticky threads.
Web rebuilding and habitat
Webs are damaged by wind, rain, and insects. Many species build a new web daily or periodically, sometimes consuming the old silk to recycle the protein. Webs play a role in regulating insect populations in fields and houses, and are used as an indicator of environmental health.