Coolest thing I've seen all week! So glad it's raining out my painting plans ... Gladly give up that progress for the nerdy coolness of this info ... "my" spider may be back this year. When did I start liking spiders?!
Copied complete from what may be my favorite magazine, Wired Science ... Ummm ... Yeah, top ten.
Spider Silk Is Strong Because It's Smart ~ Adam Mann 1Feb12. (yes, the author has a cool name)
Spider silk is well known for some spectacular properties. It is stronger than steel and tougher than Kevlar yet flexible enough to be spun into a wide variety of shapes.
New research shows that the material is not only strong but also smart.
“Spider silk has a particular way of softening and then being stiff that is really essential for it to function properly,” said engineer Markus J. Buehler of the Massachusetts Institute of Technology, who co-authored the new study, which appears in Nature Feb. 2.
A spider web provides its occupant with a home and a way to catch prey. It needs to stand up to pesky attackers and sometimes withstand hurricane-force winds. Using computer models of spider silk and experiments on the webs of common European garden spiders (Araneus diadematus), Buehler and his team found a web’s unique skills come from its ability to react differently to different stress levels.
A light wind, for instance, softens the web, allowing it to lengthen but retain its overall structure. If a larger force is applied at a specific location, such as when a particular thread is poked, the silk becomes rigid and breaks.
Furthermore, only the most extended silk threads get severed. Having small portions of the web come apart not only helps retain the overall structural integrity but actually makes the web stronger. The researchers found that removing up to a tenth of the threads at different locations allowed the structure to carry 3 to 10 percent more weight. This shows the web’s advantage over materials such as steel, which would simply break apart under such conditions.
The work provides insight into spiders’ success with catching prey, said biologist Todd A. Blackledge of the University of Akron in Ohio, who was not involved in the study. “It’s really important for the silk to stretch under impact, cradling the insect so it doesn’t bounce out,” he said.
Engineers could also apply the secrets of spider silk to other challenges, Buehler suggested. Its ability to sustain small damage without compromising the entire structure could be useful in designing virtual networks, such as the Internet, where a local node gets sacrificed during an attack to keep the whole system from going down. Understanding how its microscopic protein structure gives rise to its macroscopic properties might help in stringing together carbon nanotubes, which may one day be used to produce objects ranging from combat gear to space elevators.
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