In Germany, velvet worms shoot out sticky secretions that stiffen into strong threads under the action of force, and then can be dissolved and reformed again, making it an interesting animal for scientists at the Max Planck Institute of Colloids and Interfaces to investigate. By studying how the velvet worms make these reversible polymer fibers, they hope to someday synthesize novel recyclable materials.
While the fibers of the velvet worm aren’t as strong as spider silk, the fact that they harden when prey get stuck in the fibers making it impossible for them to escape, making the filaments very similar to nylon. The surprising finding was that the polymerized slime threads can be dissolved in water again within a few hours of drying, and they can be drawn again from the recovered slime, behaving exactly like freshly secreted velvet-worm secretion under the influence of shear forces: they hardened. Velvet worms could serve as a model for manufacturers of synthetic polymers and could conceivably teach them a lot about the sustainable production of synthetic materials.