The New York Times
July 30, 2012
Blowing in the Wind
By C. CLAIBORNE RAY
Q. I found single spider-web filaments between bushes four feet apart. How did the spider spin them over such a distance? And what happened to the rest of the web?
A. A spider relies on the wind to carry the filaments across wide intervals. But a mere four feet is a minor accomplishment for spiders. One recently discovered species from Madagascar, Darwin’s bark spider, or Caerostris darwini, habitually bridges rivers .
Spiders that build the familiar orb-shaped web usually start with a single superstrength strand called a bridge thread or bridge line. The telescoping protein structure of this silk is believed to gives it its strength.
First, the material for the bridge thread emerges from one of the spider’s specialized silk glands and is formed into a strand by its spinnerets. The loose end is drawn out by gravity or the breeze and allowed to blow in the prevailing wind, a process called kiting or ballooning.
If the strand does not make contact with something and attach to it, the spider may gobble up the strand and recycle its proteins, then try again. If the gap is bridged, the spider reinforces the strand and uses it to start the web.
A single bridge thread may be left in place overnight to mark a spider’s territory and a desirable starting spot for building a web the next day. C. CLAIBORNE RAY
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