Volumetric and lateralized differences in selected brain regions of chimpanzees (Pan troglodytes) and bonobos (Pan paniscus)
Article first published online: 16 SEP 2009
© 2009 Wiley-Liss, Inc.
American Journal of Primatology
Volume 71, Issue 12, pages 988–997, December 2009
How to Cite
Hopkins, W. D., Lyn, H. and Cantalupo, C. (2009), Volumetric and lateralized differences in selected brain regions of chimpanzees (Pan troglodytes) and bonobos (Pan paniscus). Am. J. Primatol., 71: 988–997. doi: 10.1002/ajp.20741
- Issue published online: 24 OCT 2009
- Article first published online: 16 SEP 2009
- Manuscript Revised: 27 JUL 2009
- Manuscript Accepted: 27 JUL 2009
- Manuscript Received: 6 APR 2009
- NIH grants. Grant Numbers: NS-42867, HD-56232
- brain evolution;
The two species of Pan, bonobos and common chimpanzees, have been reported to have different social organization, cognitive and linguistic abilities and motor skill, despite their close biological relationship. Here, we examined whether bonobos and chimpanzee differ in selected brain regions that may map to these different social and cognitive abilities. Eight chimpanzees and eight bonobos matched on age, sex and rearing experiences were magnetic resonance images scanned and volumetric measures were obtained for the whole brain, cerebellum, striatum, motor-hand area, hippocampus, inferior frontal gyrus and planum temporale. Chimpanzees had significantly larger cerebellum and borderline significantly larger hippocampus and putamen, after adjusting for brain size, compared with bonobos. Bonobos showed greater leftward asymmetries in the striatum and motor-hand area compared with chimpanzees. No significant differences in either the volume or lateralization for the so-called language homologs were found between species. The results suggest that the two species of Pan are quite similar neurologically, though some volumetric and lateralized differences may reflect inherent differences in social organization, cognition and motor skills. Am. J. Primatol. 71:988–997, 2009. © 2009 Wiley-Liss, Inc.