Why do different types of spiders weave different webs (e.g. funnel or orb)?
Peter Web designs have evolved over millions of years from just a few silk threads that allowed spiders to sit in a protected environment while monitoring the world outside for both prey and predators to efficient traps. Different web designs, then, in part reflect advances in trap efficiency but also where these traps are placed and what types of insects a kind of spider might expect to capture. The orb web is the most advanced of the spider webs and its open design permits spiders to place the webs up in the air currents in the flight paths of moths and butterflies. Orb webs have evolved in two major lines of spiders, in the hackled-band weavers that have a mechanically sticky web (many fine threads) and in the araneids that produce a chemically sticky spiral trap. The open space between capture lines is needed to let air pass through. Otherwise the web would be destroyed by the winds. Because of the small amount of silk used in these webs and all of the open space, the sticky silk i
