E-raamat: Attachment Structures and Adhesive Secretions in Arachnids

This book surveys attachment structures and adhesive secretions occurring in this class of animals and discusses the relationships between structure, properties, and function in the context of evolutionary trends, and biomimetic potential. Topics comprise mechanical attachment devices, such as clamps, claws, hooks, spines and wraps, as well as hairy and smooth adhesive pads, nano-fibrils, suction cups, and viscid and solidifying adhesives. Attachment is one of the major types of interactions between an organism and its environment. There are numerous studies that deal with this phenomenon in lizards, frogs, insects, barnacles, mussels and echinoderms, but the second largest class of animals, the Arachnida, was highly neglected so far. The authors demonstrated that most arachnid adhesive structures are highly analogous to those of insects and vertebrates, but there are also numerous unique developments with some intriguing working principles. Because arachnid attachment organs have

a very strong potential of technological ideas for the development of new materials and systems, inspirations from biology could also be interesting for a broad range of topics in materials and surface engineering.

1. Overview1.1 Introduction1.2 The arachnid orders1.3 Material and methods1.4 Terminology1.5 Summary and distribution of attachment principles among arachnids2 Mechanical attachment devices2.1 Claws2.2 Spines and pointed hairs2.3 Other interlocking devices2.4 Pincers and clamps2.5 Expansion anchors2.6 Lock-and-key2.7 Wrapping3 Tape- and spatula-shaped microstructures3.1 Introduction3.2 Spatulate setae3.3 Spatulate microtrichia3.4 Spatulate surface structures3.5 Micro-tapes4 Nano-Fibrils4.1 Cribellate and aciniform silk4.2 Particle catching setae4.3 Fibrillar locomotory pads lacking spatulae5 Mushroom-shaped microstructures5.1 Introduction5.2 Cuticular mushroom-shaped microstructures5.3 Mushroom shaped secretion products6 Suction cups6.1 Introduction6.2 Adanal suckers in mites6.3 Sucker-like mouth parts7 Soft adhesive pads7.1 Introduction7.2 Cushion-like arolium7.3 Disc-like arolium7.4 Transverse lip arolium7

.5 Other smooth adhesive pads8 Adhesive secretions8.1 Introduction8.2 Viscid glue8.3 Solidifying glue9 Biological function and evolutionary aspects9.1 Ontogeny and the role of maternal care9.2 Dispersal9.3. Microhabitat access and climbing demand9.4 Herbivore-plant interaction9.5 Predator-prey interaction9.6 Parasite-host interaction9.7 Sexual selection10 Comparative contact mechanics10.1 Comparative mechanics and strength of smooth and structured adhesive foot pads10.2 The contact splitting theory and the scaling of adhesive foot pads 10.3 Dry or wet adhesion?<11 Biomimetics: What can we learn from arachnids?11.1 Why geckoes are not unique11.2 Noteworthy structures and their potential for biomimetics and bioinspiration