Spider Silk Is Strong Because It’s Smart

Besides having a tensile strength stronger than steel, apparently spider silk is also a “smart” material:

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.