Spiders spin their webs from silk. It is pumped out from tiny nozzles at the back of the abdomen, which are called spinnerets. As the silk is stretched by the spider into a thread, it hardens. For its thickness, the thread becomes proportionately stronger than steel. Some of the threads are sticky, while others simply support the web. The spider is able to feel the vibrations of the web when an insect flies into it, and it runs quickly across the web to capture and subdue the prey. Usually, the insect is wrapped in silk before being eaten by the spider.
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