Sunday, January 13, 2008


I will eventually stop apologising for posting about spiders at the moment!
I've been noticing more and more of the Missing sector Orb Weavers, Zygiella x-notata spiders around recently. Those, and the Daddy Long-legs spiders, Pholcus phalangioides, in the house (well, one or two anyway).

The MSOWs are amazing in that unlike most other spiders, the female of the species tends to build their very distinctive webs all year round.
I noted a dozen or so webs yesterday, all with a female on it, and all missing a sector at the top of the orb web, with just one thick, "signal thread" through this missing sector, to the centre of the web proper.

Spiders are fascinating in my opinion.
Not only is their basic leg movement pretty well governed by hydraulics - they effectively pump fluid into their hollow legs to extend them, and use a simple muscular arrangement to bend the leg back towards the body, expelling the fluid inside - exactly like a hydraulic piston - at incredible speeds when one thinks about it.
The next time you watch a House Spider race across the floor - think about its movement in terms of hydraulics - thats pretty darn impressive in my eyes.

Not only that, there is the silk they produce.
Spiders' silk is five times stronger than steel, and thirty times stretchier than nylon.
Your average spider will spin more than 4 miles of silk in its lifetime.

Most spiders are expert web builders, even in zero gravity conditions. (Its amazing what scientists research sometimes....).
Give a spider some drugs though, and its ability to construct a decent web is impaired.
Give a spider some marijuana, (I don't know whether you can get a spider to smoke), and the spider will lose concentration have way through building a web, and leave it half-done.
Give it amphetamines - and the spider will spin faster, but with FAR less accuracy.
Give the spider coffee though, and the web-building process is most seriously impaired. In this case, the spider will just produce a random pattern of just a few threads stuck together, pretty haphazardly.
The first two resuts of drugs and spiders experiments are hardly surprising eh? The coffee experiment surprises me though...

I'll post a photograph of another Missing Sector Orb Weaver on its web above, showing its missing sector, and its signal thread above, so readers of BG can click to enlarge.

Above that, I'll post a photograph of a male Daddy Long Legs spider (with its "boxing glove" pedipalps) that I took this morning, under our bathroom sink. Once again, click on that to enlarge...

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