Laterality of manual function in foraging and positional behavior in wild indri (Indri indri)
Article first published online: 11 JAN 2005
© 2005 Wiley-Liss, Inc.
American Journal of Primatology
Volume 65, Issue 1, pages 27–38, January 2005
How to Cite
Rigamonti, M. M., Spiezio, C., Poli, M. D. and Fazio, F. (2005), Laterality of manual function in foraging and positional behavior in wild indri (Indri indri). Am. J. Primatol., 65: 27–38. doi: 10.1002/ajp.20095
- Issue published online: 11 JAN 2005
- Article first published online: 11 JAN 2005
- Manuscript Accepted: 4 AUG 2004
- Manuscript Received: 18 JUL 2003
- Indri indri;
- hand preference;
This research is based on the idea that some prosimian species are good models in which to test certain postulates of the “postural origins” theory proposed by MacNeilage and colleagues [Behavioral and Brain Sciences 10:247–303, 1987] to explain the evolution of hand preference within the order Primates. We investigated manual laterality in 16 wild indris (eight males and eight females, living in four social groups) in their habitat, the Madagascan tropical rain forest. Data were collected on two spontaneous behaviors: “branch-reach,” an action that occurs during foraging, and “higher support,” a posture typical of clingers and leapers. A total of seven subjects were significantly lateralized for branch-reach (two showed a right preference, and five showed a left preference). Four subjects were significantly lateralized for higher support, and all of them showed a right-hand preference. Most of the indris we studied showed no preference. Our research suggests that indri are at “level 1 of laterality” in the classification framework proposed by McGrew and Marchant [Yearbook of Physical Anthropology 40:201–232, 1997]. The data presented here are not discordant with the “postural origins” theory, as lateralized subjects are often in the direction predicted by MacNeilage and colleagues [Behavioral and Brain Sciences 10:247–303, 1987], but they are the minority. Am. J. Primatol. 64:27–38, 2005. © 2005 Wiley-Liss, Inc.