title: Canine length in wild male baboons: maturation, aging and social dominance rank.
abstract: Canines represent an essential component of the dentition for any heterodont mammal. In primates, like many other mammals, canines are frequently used as weapons. Hence, tooth size and wear may have significant implications for fighting ability, and consequently for social dominance rank, reproductive success, and fitness. We evaluated sources of variance in canine growth and length in a well-studied wild primate population because of the potential importance of canines for male reproductive success in many primates. Specifically, we measured maxillary canine length in 80 wild male baboons (aged 5.04-20.45 years) from the Amboseli ecosystem in southern Kenya, and examined its relationship with maturation, age, and social dominance rank. In our analysis of maturation, we compared food-enhanced baboons (those that fed part time at a refuse pit associated with a tourist lodge) with wild-feeding males, and found that food-enhanced males achieved long canines earlier than wild-feeding males. Among adult males, canine length decreased with age because of tooth wear. We found some evidence that, after controlling for age, longer canines were associated with higher adult dominance rank (accounting for 9% of the variance in rank), but only among relatively high-ranking males. This result supports the idea that social rank, and thus reproductive success and fitness, may depend in part on fighting ability mediated by canine size.
authors.affiliation: Center for the Advanced Study of Hominid Paleobiology, Department of Anthropology, The George Washington University, Washington DC, United States of America.
authors.forename: Jordi
authors.initials: J
authors.lastname: Galbany
authors.affiliation: Department of Evolutionary Anthropology, Duke University, Durham, NC, United States of America; Duke Population Research Institute, Duke University, Durham, NC, United States of America; Institute of Primate Research, National Museums of Kenya, Nairobi, Kenya; Department of Biology, Duke University, Durham, NC, United States of America.
authors.forename: Jenny
authors.initials: J
authors.lastname: Tung
authors.affiliation: Institute of Primate Research, National Museums of Kenya, Nairobi, Kenya; Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, United States of America.
authors.forename: Jeanne
authors.initials: J
authors.lastname: Altmann
authors.affiliation: Institute of Primate Research, National Museums of Kenya, Nairobi, Kenya; Department of Biology, Duke University, Durham, NC, United States of America.
authors.forename: Susan C
authors.initials: SC
authors.lastname: Alberts
mesh_terms: D000375:Aging; D000818:Animals; D003481:Cuspid / Q000033:anatomy & histology* / Q000254:growth & development*; D008297:Male; D010215:Papio / Q000033:anatomy & histology* / Q000254:growth & development*; D012741:Sexual Maturation; D012930:Social Dominance