External forces on the limbs of jumping lemurs at takeoff and landing
Article first published online: 4 APR 2005
Copyright © 2005 Wiley-Liss, Inc.
American Journal of Physical Anthropology
Volume 128, Issue 2, pages 348–358, October 2005
How to Cite
Demes, B., Franz, T. M. and Carlson, K. J. (2005), External forces on the limbs of jumping lemurs at takeoff and landing. Am. J. Phys. Anthropol., 128: 348–358. doi: 10.1002/ajpa.20043
- Issue published online: 23 SEP 2005
- Article first published online: 4 APR 2005
- Manuscript Accepted: 29 JAN 2004
- Manuscript Received: 10 OCT 2003
- NSF. Grant Number: BCS 0109331
- ground reaction force;
- Lemur catta;
- Eulemur fulvus
Ground reaction forces were recorded for jumps of three individuals each of Lemur catta and Eulemur fulvus. Animals jumped back and forth between a ground-mounted force plate and a 0.5-m elevated platform, covering horizontal distances of 0.5–2 m. In total, 190 takeoffs and 263 landings were collected. Animals typically jumped from a run up and into a run out, during which they gained or into which they carried horizontal impulse. Correspondingly, vertical impulses dominated takeoffs and landings. Peak forces were moderate in magnitude and not much higher than forces reported for quadrupedal gaits. This is in contrast to the forces for standing jumps of specialized leapers that considerably exceed forces associated with quadrupedal gaits. Force magnitudes for the lemur jumps are more comparable to peak forces reported for other quadrupeds performing running jumps. Takeoffs are characterized by higher hindlimb than forelimb peak forces and impulses. L. catta typically landed with the hindlimbs making first contact, and the hindlimb forces and impulses were higher than the forelimb forces and impulses at landing. E. fulvus typically landed with the forelimbs striking first and also bearing the higher forces. This pattern does not fully conform to the paradigm of primate limb force distribution, with higher hindlimb than forelimb forces. However, the absolute highest forces in E. fulvus also occur at the hindlimbs, during acceleration for takeoff. Am J Phys Anthropol, 2005. © 2005 Wiley-Liss, Inc.