Effective limb length and the scaling of locomotor cost in terrestrial animals.


Journal Article

Relative to body size, smaller animals use more energy to travel a given distance than larger animals, but the anatomical variable driving this negative allometry remains the subject of debate. Here, I report a simple inverse relationship between effective limb length (i.e. hip height) and the energy cost of transport (COT; J kg(-1) m(-1)) for terrestrial animals. Using published data for a diverse set of terrestrial species including birds, mammals, reptiles and arthropods, I show that between-species differences in locomotor cost are driven by differences in limb length. Notably, there is no independent effect of body mass on cost. Remarkably, effective limb length explains 98% of the observed variance in locomotor cost across a wide range of terrestrial species including mammals, birds, reptiles and arthropods. Variation about the limb-length/COT scaling relationship is attributable to taxonomic differences in limb design, with birds and arthropods exhibiting greater residuals than mammals. Differences in COT between semi-aquatic, generalist and cursorial species also corresponds to differences in leg length between these groups. These results are discussed in light of previous investigations of the limb length and locomotor cost.

Full Text

Duke Authors

Cited Authors

  • Pontzer, H

Published Date

  • May 2007

Published In

Volume / Issue

  • 210 / Pt 10

Start / End Page

  • 1752 - 1761

PubMed ID

  • 17488938

Pubmed Central ID

  • 17488938

Electronic International Standard Serial Number (EISSN)

  • 1477-9145

International Standard Serial Number (ISSN)

  • 0022-0949

Digital Object Identifier (DOI)

  • 10.1242/jeb.002246


  • eng