Jonas Wolff
Universität Greifswald, Evolutionary Biomechanics, Zoological Institute and Museum & School of Natural Sciences, Macquarie University, Sydney, Australia
Germany
Tough threads, ballistic webs and bungee-jumps: evolutionary biomechanics of spider extended phenotypes
Spider silk is among the toughest known materials, enabling spiders to construct multi-functional architectures with a minimum of material investment. Spiders use these architectures (threads, webs, retreats and egg cases) as extended interfaces, which may impressively enhance predatory, defensive and locomotor capabilities. Spiders typically produce multiple types of silk secretions in differentiated glandular systems, that are connected to spinnerets – leg-like appendages equipped with various muscles that enable fine-scale movements. In this talk I give an overview about our latest research on how the structure and function of the spider spinning apparatus, silks and silk architectures changed over 400 million years of spider evolution. In particular, I will demonstrate how changes in spinning apparatus morphology enabled the evolution of novel behaviours and tougher silk threads. Further, I will show examples of how spiders may use silk architectures for power amplification, to subdue large prey and for rapid escape manoeuvres. These examples broaden the perspective of functional morphology, which does not only apply to body parts, but also to extended phenotypes, such as architectures formed by secretions.
