University of Bayreuth, Press release no. 175/2023, 20.12.2023
Tracking down the influence of environmental factors on spider silk
Whether spider silk is stronger and tougher depends on the environmental influences to which it is exposed. Prof Dr Thomas Scheibel, Chair of Biomaterials at the University of Bayreuth, and his team have now published a study in which they show that spider webs are particularly robust in areas of heavy rainfall. They are now presenting the results of the study with 50 spider species in the journal Current Biology.
In the course of evolution, spiders have developed "orb webs" to catch their prey. The radii of these "orb webs" are particularly important: they absorb the energy of prey collisions. These so-called major ampullate silks, also known as dragline silk, are tougher than most natural and man-made fiber materials. In the latest study by Prof Dr Thomas Scheibel, Chair of Biomaterials at the University of Bayreuth, silk from 50 spider species in Colombia was examined and compared. The aim was to understand how the environment affects the mechanical properties of silk. "It was the first study on spider silks to analyse entire area-wide environmental factors along climatic and altitudinal gradients," explains Scheibel. "The results show that spiders in regions with a lot of heavy rainfall have stronger silk threads than spiders that live in regions, in which heavy rain events are less frequent."
This means that spider silk from regions with strong rainfall can also absorb more energy. This applies not only between different spider species, but also within the same species. "It is likely that the mechanical properties of the silk have been optimised in areas with heavy rainfall in order to minimise damage to the webs and the associated energetic loss for the spider," says Scheibel. This knowledge allows material scientists to direct their search for new exceptional silks more effectively.
Prof Dr Thomas Scheibel, Prof Dr Heike Feldhaar and Charlotte Hopfe from the University of Bayreuth have now published the results of this study in Current Biology under the title "Impact of environmental factors on spider silk properties". They worked together with research partners from Spain, Colombia and Göttingen and were funded by the German Academic Exchange Service (DAAD), the Research Foundation of the German People and the Office of Naval Research Global (ONRG).
Charlotte Hopfe, Bryan Ospina-Jara, Thilo Schulze, Marta Tischer, Diego Morales, Vivien Reinhartz, Rashin Eshghi Esfahani, Carlos Valderrama, José Pérez-Rigueiro, Christoph Bleidorn, Heike Feldhaar, Jimmy Cabra-García, Thomas Scheibel, "Impact of environmental factors on spider silk properties", Current Biology, 2023, DOI: https://doi.org/10.1016/j.cub.2023.11.043.