Madagascar’s Darwin Bark Spider (Caerostris darwini) spins the largest and strongest of webs.

The webbing is ten times stronger than Kevlar, the substance used for reinforcing bulletproof vests, making it the strongest known biological substance. The spiders cast strands of the webbing into the wind, allowing it to be carried as far as 80 feet away before anchoring to something solid on the other side.

The bark spider uses this strong webbing and innovative construction technique to extend webs across rivers, covering as much as 30 square feet, hanging from the 80-foot anchor lines. These webs are about as long as two city buses.

The webs are twice as strong as other orb spiders, and are strong enough to catch a bird or bat.

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