Wednesday, March 04, 2009

Cloud crawler

Look at this superb specimen, an argiope, the size of a child's hand, apparently hanging from a cloud. What you don't see is its orb web, a meter in diameter, closely strung of the finest thread -- so fine that it doesn't show up in my photograph.

"What refinement of art for a mess of flies!" exclaimed the great entomologist J. Henri Fabre, in his The Life of the Spider. "Nowhere, in the whole animal kingdom, has the need to eat inspired a more cunning industry."

Spiders have been spinning silk for several hundred million years. A 110 million-year-old piece of Spanish amber shows a fly and a mite trapped by strands of spider silk, apparently from a spiral web. With the explosive diversification of flowering plants and pollinating insects, spiders were quick to evolve orb webs with which to fish the skies.

The Calatravan gift of cable architecture is in their genes. Hatchling spiders spin webs that rival the finest work of adults. Says Fabre: "There are no masters or apprentices in their guild; all know their craft from the moment that the first thread is laid."

And if that doesn't make your head spin, nothing will.