The next time you brush aside a spiderweb, you might want to meditate on its delicate strength—if human-size, it would be tough enough to snag a jetliner. Now, scientists know just how these silken strands get their power: through thousands of even smaller strands that stick together to form this critter’s clingy trap.
To find out how most spider silk is five times stronger than steel, scientists analyzed the silk that venomous brown recluse spiders use to create their ground webs and hold their eggs, using an atomic force microscope. They found that each strand—which is 1000 times thinner than a human hair—is actually made up of thousands of nanostrands, only 20 millionths of a millimeter in diameter, they reported last month in ACS Macro Letters. Just like a tiny cable, each silk fiber is entirely composed of parallel nanostrands, which they measured to be at least 1 micron long. That may not sound very lengthy, but on a nanoscale, it’s at least 50 times as long as these fibers are wide—and researchers believe they could stretch even further.To read more, click here.