TY - JOUR
T1 - Primate origins
T2 - Evolutionary change in digital ray patterning and segmentation
AU - Hamrick, Mark W.
N1 - Funding Information:
Drs R. MacPhee, C. Norris, R. Randall, and especially P. Mikkelsen are thanked for their curatorial assistance with the Bluntschli collection at the American Museum of Natural History, New York. Ms Linda Gordon and Drs J. Mead and A. Gardner provided curatorial assistance at the Smithsonian Institution and Dr B. Latimer and Mr L. Jellema are thanked for curatorial assistance at the Cleveland Museum of Natural History. I am grateful to Dr W. J. Krause III, University of Missouri, Dr K. K. Smith, Duke University, and Dr Martine Perret, Muséum National d’Histoire Naturelle (Brunoy), for generously donating opossum specimens and to Dr G. Gunnell, University of Michigan, for sharing unpublished data on hand proportion in Plesiadapis cookei. Drs M. Dagosto and J. G. M. Thewissen provided helpful comments that improved the manuscript. Funding for this research was provided by Kent State University and the National Science Foundation.
PY - 2001
Y1 - 2001
N2 - This study presents evidence that the first primates share with extant lemurs, tarsiers, and anthropoids hand proportions unlike those of their close relatives, the tree shrews (Scandentia), colugos (Dermoptera), and plesiadapiforms. Specifically, early primates as well as modern strepsirhines and haplorhines have relatively short metacarpals and long proximal phalanges giving them a grasping, prehensile hand. Limb development was studied in the primate Microcebus murinus and a comparative sample of rodents, artiodactyls, and marsupials to investigate the role of embryonic patterning in the morphogenesis and evolution of primate hand proportions. Comparative analysis shows that the derived finger proportions of primates are generated during the early phases of digital ray patterning and segmentation, when the interzone cells marking the presumptive metacarpo- and interphalangeal joints first appear. Interspecific variation in relative digit and metapodial proportions therefore has high developmental penetrance; that is, adult differences are observed at early ontogenetic stages. The paleontological, comparative, and developmental data are therefore consistent with the hypothesis that the early Cenozoic origin of primates involved an evolutionary change in digital ray pattern formation ultimately yielding a grasping, prehensile hand.
AB - This study presents evidence that the first primates share with extant lemurs, tarsiers, and anthropoids hand proportions unlike those of their close relatives, the tree shrews (Scandentia), colugos (Dermoptera), and plesiadapiforms. Specifically, early primates as well as modern strepsirhines and haplorhines have relatively short metacarpals and long proximal phalanges giving them a grasping, prehensile hand. Limb development was studied in the primate Microcebus murinus and a comparative sample of rodents, artiodactyls, and marsupials to investigate the role of embryonic patterning in the morphogenesis and evolution of primate hand proportions. Comparative analysis shows that the derived finger proportions of primates are generated during the early phases of digital ray patterning and segmentation, when the interzone cells marking the presumptive metacarpo- and interphalangeal joints first appear. Interspecific variation in relative digit and metapodial proportions therefore has high developmental penetrance; that is, adult differences are observed at early ontogenetic stages. The paleontological, comparative, and developmental data are therefore consistent with the hypothesis that the early Cenozoic origin of primates involved an evolutionary change in digital ray pattern formation ultimately yielding a grasping, prehensile hand.
KW - Archonta
KW - Climbing
KW - Hand morphology
KW - Limb development
KW - Pattern formation
KW - Prehensility
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U2 - 10.1006/jhev.2001.0467
DO - 10.1006/jhev.2001.0467
M3 - Article
C2 - 11312586
AN - SCOPUS:0035074837
SN - 0047-2484
VL - 40
SP - 339
EP - 351
JO - Journal of Human Evolution
JF - Journal of Human Evolution
IS - 4
ER -