Montana Public Radio

Bug Bytes: Spider Silk

Feb 5, 2019

Thanks to the children’s novel Charlotte’s Web by E.B. White, most of us are familiar with the circular shape of an orb weaver spider web. Charlotte certainly had no trouble creating a new web overnight, but it might be more complicated than you think.

As masters of web construction, orb-weaving spiders can produce up to seven different types of silk. Each silk comes from a specific gland and they are all suited for specific tasks.

  • There’s a strong and elastic silk (like a sticky glue) used to secure the web.
  • Dragline silk is used to make the strong spokes of the web and is used as a lifeline for the spider to hang from.
  • There’s an extremely elastic silk that can stretch up to 300 percent without breaking.
  • There’s silk that stays in a liquid form and is used like a glue.
  • There’s silk that’s used like cement, to latch other silks together and anchor the frame of the web to its surroundings.
  • And there’s a special swathing silk that’s used to wrap and immobilize prey.
  • Females also produce an additional type of silk for the strong, outer cover to their egg sacks.

And when I say spider silk is strong, I mean it’s strong:

  • It’s up to 10 times stronger than Kevlar, the material used to make bullet-proof vests.
  • Researchers at the University of Singapore have said that one strand of pencil-thick spider silk would stop a 747 in flight.

So the next time you see an orb weaver’s spider web, stop to admire its amazing structure and the incredible animal responsible for it. And be glad it’s intended for things much smaller than you.

BugBytes is made possible by the Missoula Butterfly House and Insectarium, and Montana Public Radio. This show is also supported by funding from the Greater Montana Foundation: Encouraging communication on issues, trends and values of importance to Montanans.