Science Questions

How do spiders spring webs across gaps?

In my garden, which is quite exposed, I find spiders webs where there’s no access between point A and point B where they’ve made their web. I’ve even put cameras up to see how they do it and I just can’t catch them in the act. So how do they get across these big gaps to make these webs? Terrance Hayle, Zandwort

Spiders produce a very light and floaty piece of silk from their spinneretts and just wave it out in the breeze.  the wind will carry it away and if it actually sticks on to something a bit further away it can start building its web.  It’s all a bit chancy really, it’s not a determined thing.  Once that first little thin line has stuck on they’ll climb along it and reinforce that first strut.  Then they actually use their own bodies and footsteps to measure along and count back to the middle of it to get to the central point.  Then they drop a sort of plumb line using themselves as the weight.  They’ll go down like an absailer down a cliff.  They absail down that line to make a Y-shape and that is the scaffolding they’ll fill in with different patterns.

October 2007