Abstract
This study examined the cranial affinities of all extant hominoids using 3D geometric morphometric analysis. A least squares Procrustean superimposition was used to eliminate differences due to location, orientation, and size. Because of a persistent correlation between centroid size and shape variation, an allometric size adjustment was also applied to these data. Phenetic affinities were then examined through a battery of multivariate statistical analyses. Results of this study indicate a strong affinity between Hylobates and Gorilla; Pan is also similar to these genera, while Pongo and Homo are each very different. The autapomorphic morphologies of orangutan and modem human crania have been well established from previous studies. The similarity between Hylobates and Gorilla, however, has important implications for studies of hominoid morphology. First, these results suggest that African ape crania - and particularly those of Gorilla - retain an overall morphology that is conservative among hominoids. Secondly, this similarity suggests that character coding of cranial features may tend to overestimate the degree of polymorphism among extant apes. This study concludes that allometry may play a greater role in the morphogenesis of hominoid cranial variation than has been previously thought. While this problem likely has negligible impact on systematic studies of extant hominoids, it seriously affects our ability to place fossil taxa within a phylogenetic framework.
Original language | English (US) |
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Pages (from-to) | 429-433 |
Number of pages | 5 |
Journal | Annals of Anatomy |
Volume | 186 |
Issue number | 5-6 |
DOIs | |
State | Published - Dec 2004 |
Externally published | Yes |
Bibliographical note
Funding Information:Acknowledgements. I am most grateful to Drs. Thomas Koppe and Todd Rae for organizing this workshop and inviting me to participate. Their comments and those of all participants were very helpful regarding this and other projects. Special thanks to the crew from Vienna for much advice, interest, and constructive dialog. I am grateful to all who provided access to specimens in their care. In addition, I thank Eric Delson, Terry Harrison, Steve Frost, Michelle Singleton, and Leslie Cecil for comments and assistance on various aspects of this study. This research was partially funded by NSF grants to NYCEP (DBI 9602234) and the NYCEP Morphometrics Group (ACI 9982351). Additional funding was provided through a travel grant from Baylor University. This is NYCEP Morphometries contribution number 13.
Keywords
- Allometry
- Cranial morphology
- Hominoids
- Morphometrics