Whole body mechanics of stealthy walking in cats.
Repository Usage Stats
The metabolic cost associated with locomotion represents a significant part of an animal's metabolic energy budget. Therefore understanding the ways in which animals manage the energy required for locomotion by controlling muscular effort is critical to understanding limb design and the evolution of locomotor behavior. The assumption that energetic economy is the most important target of natural selection underlies many analyses of steady animal locomotion, leading to the prediction that animals will choose gaits and postures that maximize energetic efficiency. Many quadrupedal animals, particularly those that specialize in long distance steady locomotion, do in fact reduce the muscular contribution required for walking by adopting pendulum-like center of mass movements that facilitate exchange between kinetic energy (KE) and potential energy (PE). However, animals that are not specialized for long distance steady locomotion may face a more complex set of requirements, some of which may conflict with the efficient exchange of mechanical energy. For example, the "stealthy" walking style of cats may demand slow movements performed with the center of mass close to the ground. Force plate and video data show that domestic cats (Felis catus, Linnaeus, 1758) have lower mechanical energy recovery than mammals specialized for distance. A strong negative correlation was found between mechanical energy recovery and diagonality in the footfalls and there was also a negative correlation between limb compression and diagonality of footfalls such that more crouched postures tended to have greater diagonality. These data show a previously unrecognized mechanical relationship in which crouched postures are associated with changes in footfall pattern which are in turn related to reduced mechanical energy recovery. Low energy recovery was not associated with decreased vertical oscillations of the center of mass as theoretically predicted, but rather with posture and footfall pattern on the phase relationship between potential and kinetic energy. An important implication of these results is the possibility of a tradeoff between stealthy walking and economy of locomotion. This potential tradeoff highlights the complex and conflicting pressures that may govern the locomotor choices that animals make.
Published Version (Please cite this version)10.1371/journal.pone.0003808
Publication InfoBishop, Kristin L; Pai, Anita K; & Schmitt, Daniel (2008). Whole body mechanics of stealthy walking in cats. PLoS One, 3(11). pp. e3808. 10.1371/journal.pone.0003808. Retrieved from https://hdl.handle.net/10161/4508.
This is constructed from limited available data and may be imprecise. To cite this article, please review & use the official citation provided by the journal.
More InfoShow full item record
Professor in the Department of Evolutionary Anthropology
My primary interest is in the evolution of primate locomotion. I am studying the mechanics of movement in primates and other vertebrates in the laboratory to understand the relationship between movement and postcranial morphology, and the unique nature of primates among mammals. Current projects include the origins of primate locomotion and the evolution of vertebrate bipedalism.