title: Fluctuating and directional asymmetry in the long bones of captive cotton-top tamarins (Saguinus oedipus).
abstract: OBJECTIVE
  Skeletal asymmetries reflect developmental stability and mechanical, functional, and physiological influences on bone growth. In humans, researchers have documented the greatest limb bone bilateral asymmetry in diaphyseal breadths, with less asymmetry in articular and maximum length dimensions. However, it remains unclear as to whether the pattern observed for humans is representative of nonhuman primates, wherein bilateral loading may minimize directional asymmetry. This study adds to the small body of asymmetry data on nonhuman primates by investigating patterns of long bone asymmetry in a skeletal sample of Saguinus oedipus (cotton-top tamarin).
  
  
  METHODS
  Humeri, radii, ulnae, femora, and tibiae of 76 adult captive cotton-top tamarin skeletons (48 males, 28 females) were measured bilaterally. We included maximum length, midshaft diaphyseal breadths, and at least one articular measurement for each bone to assess directional (DA) and fluctuating asymmetry (FA) in each dimension.
  
  
  RESULTS
  Most dimensions exhibit significant FA, and very few have significant DA; DA is limited to the lower limb, especially in knee dimensions. Overall, the magnitudes of asymmetry in tamarins have a consistent ranking that follows the same pattern as found in humans.
  
  
  CONCLUSIONS
  This first study of DA and FA among multiple dimensions throughout the limbs of a non-hominoid primate suggests that previously-reported patterns of human bilateral asymmetry are not exclusive to humans. The results further indicate potential underlying differences in constraints on variation within limb bones. While processes shaping variation await further study, our results argue that different long bone dimensions may reflect dissimilar evolutionary processes.
authors.affiliation: Department of Anatomy, Ross University School of Medicine, Portsmouth, Dominica.|Department of Anthropology, The University of Tennessee, Knoxville, TN.
authors.forename: Nicole M
authors.initials: NM
authors.lastname: Reeves
authors.affiliation: Department of Anthropology, The University of Tennessee, Knoxville, TN.
authors.forename: Benjamin M
authors.initials: BM
authors.lastname: Auerbach
authors.affiliation: Center for Functional Anatomy and Evolution, Johns Hopkins University School of Medicine, Baltimore, MD.
authors.forename: Adam D
authors.initials: AD
authors.lastname: Sylvester
mesh_terms: D000818:Animals; D000885:Anthropology, Physical; D001842:Bone and Bones / Q000033:anatomy & histology* / Q000473:pathology*; D005260:Female; D008297:Male; D012452:Saguinus / Q000033:anatomy & histology*
keywords: developmental noise; limb development; measurement error; nondirectional asymmetry; plasticity