, Volume 48, Issue 3, pp 171–178

Femur length, body mass, and stature estimates of Orrorin tugenensis, a 6 Ma hominid from Kenya

  • Masato Nakatsukasa
  • Martin Pickford
  • Naoko Egi
  • Brigitte Senut
Original Article

DOI: 10.1007/s10329-007-0040-7

Cite this article as:
Nakatsukasa, M., Pickford, M., Egi, N. et al. Primates (2007) 48: 171. doi:10.1007/s10329-007-0040-7


To understand the palaeobiology of extinct hominids it is useful to estimate their body mass and stature. Although many species of early hominid are poorly preserved, it is occasionally possible to calculate these characteristics by comparison with different extant groups, by use of regression analysis. Calculated body masses and stature determined using these models can then be compared. This approach has been applied to 6 Ma hominid femoral remains from the Tugen Hills, Kenya, attributed to Orrorin tugenensis. It is suggested that the best-preserved young adult individual probably weighed approximately 35–50 kg. Another fragmentary femur results in larger estimates of body mass, indicative of individual variation. The length of the femur of the young adult individual was estimated, by using anthropoid-based regression, to be a minimum of 298 mm. Because whole-femur proportions for Orrorin are unknown, this prediction is conservative and should be revised when additional specimens become available. When this predicted value was used for regression analysis of bonobos and humans it was estimated to be 1.1–1.2 m tall. This value should, however, be viewed as a lower limit.


Orrorin tugenensisBody-mass estimateLimb lengthFemurBipedalism

Copyright information

© Japan Monkey Centre and Springer 2007

Authors and Affiliations

  • Masato Nakatsukasa
    • 1
  • Martin Pickford
    • 2
  • Naoko Egi
    • 3
  • Brigitte Senut
    • 4
  1. 1.Laboratory of Physical Anthropology, Graduate School of ScienceKyoto UniversitySakyo, KyotoJapan
  2. 2.Collège de France and USM 203UMR 5143 CNRSParisFrance
  3. 3.Japan Monkey CentreInuyama, AichiJapan
  4. 4.Département Histoire de la Terre (Paléontologie) Muséum National d’Histoire NaturelleUSM 203, UMR 5143 du CNRSParisFrance