The triangle weaver (Hyptiotes cavatus) captures prey with a tensioned three-sided web it holds and then releases to let the web snap forward. Scientists discovered the web’s dragline silk contains up to 24.3% of the amino acid proline, an unusually high level that likely gives the silk its springy recoil. Proline’s ring-shaped side chain disrupts regular protein folding and appears to produce extreme elasticity. These molecular insights could help engineers design improved synthetic biomaterials for medicine, optics, and protective equipment.
Spring-Loaded Silk: How the Triangle Weaver’s Proline-Rich Web Snaps Up Prey
The triangle weaver (Hyptiotes cavatus) captures prey with a tensioned three-sided web it holds and then releases to let the web snap forward. Scientists discovered the web’s dragline silk contains up to 24.3% of the amino acid proline, an unusually high level that likely gives the silk its springy recoil. Proline’s ring-shaped side chain disrupts regular protein folding and appears to produce extreme elasticity. These molecular insights could help engineers design improved synthetic biomaterials for medicine, optics, and protective equipment.
09:23, 07.11.2025Science
Spring-Loaded Silk: The Triangle Weaver’s Ingenious Trap
The triangle weaver spider (Hyptiotes cavatus) gets its name from the tiny three-sided web it constructs and then tension-locks to ambush prey. The spider fastens two corners of the triangular web to surrounding supports while holding the third corner in its jaws or legs, pulling it back to form a taut, elastic platform. When an insect blunders in, the spider releases that corner and the whole triangle snaps forward, recoiling around the prey in a motion faster than the spider’s own muscles can contract.
What makes the silk so springy?
Spider silk is made of proteins called spidroins, and different silk types serve different roles—sticky silk to trap insects, lightweight silk for ballooning, and strong dragline silk to anchor webs. Researchers studying the triangle weaver’s dragline silk found an unusually high level of the amino acid proline in its spidroins: up to 24.3%, the highest proportion reported for any spider silk so far.
Proline is unusual because its side chain forms a ring that bonds back to the protein backbone. That ringed structure disrupts regular folding and is believed to give the silk its exceptional elasticity and spring-like recoil.
Why it matters beyond spiders
Understanding how specific amino acids like proline tune silk mechanics helps materials scientists mimic or improve these properties. Human uses of spider-silk-inspired materials already include medical sutures and scaffolds, components in optical devices, and high-performance fibers for protective gear. By pinpointing molecular features that produce extreme stretchiness, researchers can design better synthetic biomaterials for medicine, optics, and personal protection.
Originally reported by Nautilus.