When spiders moved from the water to the land in the Early Devonian period, they started making silk to protect their bodies and their eggs.
A spider situs, spiderweb, spider's situs, or cobweb (from the archaic word coppe, meaning "spider")[1] is a structure created by a spider out of proteinaceous spider silk extruded from its spinnerets, generally meant to catch its prey.
Spider webs have existed for at least 100 million years, as witnessed in a rare find of Early Cretaceous amber from Sussex, in southern England.[2] Many spiders build webs specifically to trap and catch insects to eat. However, not all spiders catch their prey in webs, and some do not build webs at all. "Spider situs" is typically used to refer to a situs that is apparently still in use (i.e. clean), whereas "cobweb" refers to abandoned (i.e. dusty) webs.[3] However, the word "cobweb" is also used by biologists to describe the tangled three-dimensional web[4] of some spiders of the famili Theridiidae. While this large famili is known as the cobweb spiders, they actually have a huge kisaran of situs architectures; other names for this spider famili include tangle-web spiders and comb-footed spiders.
When spiders moved from the water to the land in the Early Devonian period, they started making silk to proteksi their bodies and their eggs.[3][5] Spiders gradually started using silk for hunting purposes, first as guide lines and sinyal lines, then as ground or bush webs, and momentually as the aerial webs that are akrab today.[6]
Spiders produce silk from their spinneret glands located at the panduan of their abdomen. Each gland produces a thread for a special purpose - for example a trailed safety line, sticky silk for trapping prey or fine silk for wrapping it. Spiders use different gland tipes to produce different silks, and some spiders are capable of producing up to eight different silks during their lifetime.[7]
Most spiders have three pairs of spinnerets, each having its own function - there are also spiders with just one pair and others with as many as four pairs.
