Glowworms Spit Out Urine Ingredient to Make Webs Sticky

By Laura Geggel, Senior Writer | December 15, 2016 02:35pm ET

Baby glowworms could be the interior designers of the cave world, if it weren't for their morbid machinations. These developing worms sit inside a tube of mucus on cave ceilings, sending out a curtain of sticky threads that look like sparkling beaded necklaces.

The purpose of the dazzling threads, rather than to enchant cave homes, is to trap unsuspecting insects. And now, researchers think they may have found the secret ingredient in the worms' traps: urea from their guts. 

The urea allows moisture in the humid cave to form droplets on the glowworms' secreted threads, the researchers found. These sticky, watery droplets trap insects drawn toward the blue-green light produced by the glowworms, the researchers said.

Baby glowworms could be the interior designers of the cave world, if it weren't for their morbid machinations. These developing worms sit inside a tube of mucus on cave ceilings, sending out a curtain of sticky threads that look like sparkling beaded necklaces.

The purpose of the dazzling threads, rather than to enchant cave homes, is to trap unsuspecting insects. And now, researchers think they may have found the secret ingredient in the worms' traps: urea from their guts. 

The urea allows moisture in the humid cave to form droplets on the glowworms' secreted threads, the researchers found. These sticky, watery droplets trap insects drawn toward the blue-green light produced by the glowworms, the researchers said. 

It's about time scientists solved this sticky mystery, said study co-lead researcher Janek von Byern, a postdoctoral fellow at the Institute of Zoology at the University of Vienna and the Ludwig Boltzmann Institute for Experimental and Clinical Traumatology in Austria.

Continued