While I'm yet to catch up with the Wasp Spider, Argiope bruennichi, I have long puzzled over the stabilimentum, a structure produced these spiders to decorate their orb webs. A new study shows that stabilimenta induce negligible delays in prey perception for transverse vibrations and only minor delays for normal and tangential vibrations, primarily due to the added inertial mass. However, for tangential vibrations, the presence of stabilimenta may enhance the spider’s ability to localize prey due to increased connectivity at the center of the orb web. It's an interesting finding but it doesn't eliminate the possibility of other functions, such as making these large webs more visible and so less subject to damage by animals blundering through them.
Greco G, Dal Poggetto VF, Lenzini L, Castellucci F, Pugno NM (2025) The effect of different structural decoration geometries on vibration propagation in spider orb webs. PLoS One 20(10): e0332593. https://doi.org/10.1371/journal.pone.0332593
