How does a spider "figure out" on what plane to construct the web?

Most webs lie in a vertical plane, or slightly diagonal in relation to the ground underneath it. Why not horizontal? Is the spider capable of detecting gravity? Wind currents?How does a spider "figure out" on what plane to construct the web?Of course spiders sense gravity and wind. The spider webs you鈥檙e speaking of are, I assume, the common orb web. This web is built only by spiders in the family Araneidae. This is the third largest family of spiders and probably the most familiar. You should understand that there are at least 67 other families of spiders with widely different habits 鈥?some make no webs, some make horizontal webs, sheet webs, funnel webs, bowl webs, etc. There鈥檚 about 40,000 known species of spiders (that鈥檚 probably 20% of the total number of existing species). There are about 3,000 described orb web weavers.



To answer your question, an orb weaver can鈥檛 see more than a few inches and picks its spot using cues that are not entirely understand 鈥?but a part of the process is random. Spiders weave webs wherever they happen to be. Over 90% of any clutch of spider eggs never makes it to maturity; part of this mortality is due to just bad luck 鈥?the spider weaves a web in the wrong place and starves to death (or is picked off by a bigger predator).



To make a web they use the wind to send a sticky thread of silk to some nearby anchor. If they鈥檙e lucky, the wind finds a nice spot where the strand sticks tightly. The spider then anchors the near end and the walks across this first vertical line, strengthens it and then hangs from the middle, dropping straight down to anchor the web wherever they land. They may locate this anchor away from vertical if they have to crawl to a good anchoring spot or the wind blows them to the side. They climb back up this drop line and now have a Y-shaped web. The spider fills this out into the familiar orb shape. The fact that they drop from the center of the first strand ensures a near vertical web. If the wind doesn鈥檛 cooperate or they can鈥檛 find good anchoring spots, they try again, and again, until they get it or starve to death trying.How does a spider "figure out" on what plane to construct the web?
Vertical webs catch much less garbage such as leavesHow does a spider "figure out" on what plane to construct the web?It tries to find out the most probable path of the preys . The plane is defined by the shortest distance between the anchor pointsHow does a spider "figure out" on what plane to construct the web?
Of course a spider can detect gravity, he knows if he is falling.How does a spider "figure out" on what plane to construct the web?They use laptops and gps technology.