The Laetoli footprints and early hominin locomotor kinematics.

Journal Article (Journal Article)

A critical question in human evolution is whether the earliest bipeds walked with a bent-hip, bent-knee gait or on more extended hindlimbs. The differences between these gaits are not trivial, because the adoption of either has important implications for the evolution of bipedalism. In this study, we re-examined the Laetoli footprints to determine whether they can provide information on the locomotor posture of early hominins. Previous researchers have suggested that the stride lengths of Laetoli hominins fall within the range of modern human stride lengths and therefore, Laetoli hominins walked with modern-human-like kinematics. Using a dynamic-similarity analysis, we compared Laetoli hominin stride lengths with those of both modern humans and chimpanzees. Our results indicate that Laetoli hominins could have used either a bent-hip, bent-knee gait, similar to a chimpanzee, or an extended-hindlimb gait, similar to a human. In fact, our data suggest that the Laetoli hominins could have walked near their preferred speeds using either limb posture. This result contrasts with most previous studies, which suggest relatively slow walking speeds for these early bipeds. Despite the many attempts to discern limb-joint kinematics from Laetoli stride lengths, our study concludes that stride lengths alone do not resolve the debate over early hominin locomotor postures.

Full Text

Duke Authors

Cited Authors

  • Raichlen, DA; Pontzer, H; Sockol, MD

Published Date

  • January 2008

Published In

Volume / Issue

  • 54 / 1

Start / End Page

  • 112 - 117

PubMed ID

  • 17804036

Electronic International Standard Serial Number (EISSN)

  • 1095-8606

International Standard Serial Number (ISSN)

  • 0047-2484

Digital Object Identifier (DOI)

  • 10.1016/j.jhevol.2007.07.005

Language

  • eng