TY - JOUR A1 - Humphrey, Joseph A. C. A1 - Barth, Friedrich G. T1 - Medium flow-sensing hairs : biomechanics and models T2 - Advances in insect physiology N2 - Arthropods use fluid medium motion-sensing filiform hairs on their exoskeleton to detect aerodynamic or hydrodynamic stimuli in their surroundings that affect their behaviour. The hairs, often of different lengths and organized in groups or arrays, respond to particular fluid motion amplitudes and frequencies produced by prey, predators, or conspecifics, even in the presence of background noise peculiar to the environment. While long known to biologists and experimentally investigated by them, it is only relatively recently that comprehensive physical-mathematical models have emerged offering an alternative methodology for investigating the biomechanics of filiform hair motion. These models have been developed and applied to quantitatively predict the performance characteristics of filiform hairs in air and water as a function of the relevant parameters that affect their physical behaviour. They even allow the exploration of possible biological evolutionary paths for filiform hair changes resulting from physical selection pressures. In this chapter we review the state of knowledge of filiform hair biomechanics and discuss two physical-mathematical models to predict hair dynamical behaviour. One modelling approach is analytically exact, serving for quantitative purposes, while the other, derived from it, is approximate, serving for qualitative guidance concerning the parameter dependencies of hair motion. Using these models we look in turn at the influence of these parameters and the fluid media physical properties on hair motion, including the possibility of medium-facilitated viscous coupling between hairs. The models point to areas where data is currently lacking and future research could be focused. In addition, new results are presented pertaining to transient tlows. We qualitatively explore the possibility of an overlapping water-air niches adaptation potential that may explain how, over many generations, the filiform hairs of an arthropod living in water could have evolved to function in air. Because flow-sensing hairs have served to inspire corresponding artificial medium motion microsensors, we discuss recent advances in this area. Significant challenges remain to be overcome, especially with respect to the materials and fabrication techniques used. In spite of the impressive technological advances made, nature still remains unrivalled. Y1 - 2011 UR - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/20727 UR - https://nbn-resolving.org/urn:nbn:de:hebis:30-86263 SN - 0065-2806 IS - 34 SP - 1 EP - 80 ER -