have grown to a decent size. Even a bumbling old amateur naturalist can
point a digital camera in the right direction and try to work out how they
do things. If one is stealthy she will carry on weaving her web.
Her eight feet move from string to string with the nimbleness of a concert
pianist. It is like watching someone knitting at speed. She has already laid
down the 'warp' like the spokes of a bicycle wheel. The web is on a 45
degree slope and she is hanging on the underside with her eight feet. She
moves around in a clockwise direction paying out silk from her spinneret and
spot-welding this 'weft' to each of the radial spokes. She does this at
speed and, as far as I can see, blindly. Her eyes are on the front of her
head and she can't see her bottom.( Neither can we, thank goodness).
It seems that her rear pair of feet do a lot of the steadying and
positioning of the warp threads so the spinneret hits the right spot.
The more one looks at things like this, the more questions one asks
oneself. How, for goodness sake, do an orb spider's delicate- looking feet
cling to the web so deftly? One false move and those incredibly spiny legs
will surely become fatally entangled. Well, look no further than Google.
Amongst all the stuff about spider bites etc. I eventually found an
excellent article by an Australian describing these special hook-like claws,
one to each foot, that are used to lock on to the silk threads. Question
answered.
Peter Byles
Most orb-web spiders have stickiness only on the spiral threads, which means she can dash quickly to the centre to locate the prey through vibrations.
ReplyDeleteIn the last week of November I saw both Zygiella x-notata and Araneus diadematus actively web building in Pembroke Dock. They may still be doing so despite cold weather.