TY - JOUR
T1 - How much more would KNM-WT 15000 have grown?
AU - Ruff, Christopher B.
AU - Burgess, M. Loring
N1 - Funding Information:
We would like to thank the curators of the Powell-Cotton Museum, Royal Museum of Central Africa, Smithsonian Institution, and Harvard Museum of Comparative Zoology for their assistance in making available comparative specimens for study. Supported by grants from the Wenner-Gren Foundation for Anthropological Research (#8657) and the National Science Foundation (#BCS-1316104). The manuscript benefitted from careful reading by three reviewers.
Publisher Copyright:
© 2014 Elsevier Ltd.
PY - 2015/3/1
Y1 - 2015/3/1
N2 - Because of its completeness, the juvenile Homo ergaster/erectus KNM-WT 15000 has played an important role in studies of the evolution of body form in Homo. Early attempts to estimate his adult body size used modern human growth models. However, more recent evidence, particularly from the dentition, suggests that he may have had a more chimpanzee-like growth trajectory. Here we re-estimate his adult stature and body mass using ontogenetic data derived from four African ape taxa: Pan troglodytes troglodytes, Pan troglodytes schweinfurthii, Pan paniscus, and Gorilla gorilla gorilla. The average percentage change in femoral and tibial lengths and femoral head breadth between individuals at the same stage of dental development as KNM-WT 15000 - eruption of M2s but not M3s - and adult individuals with fully fused long bone epiphyses, was determined. Results were then applied to KNM-WT 15000, and his adult size estimated from skeletal dimensions using modern human prediction formulae. Using this approach, adult stature best estimates of 176-180cm and body mass best estimates of 80-83kg were obtained. These estimates are close to those estimated directly from longitudinal changes in body length and body mass between 8 and 12 years of age in chimpanzees, the suggested chronological equivalent to KNM-WT 15000's remaining growth period. Thus, even using an African ape growth model, it is likely that KNM-WT 15000 would have attained close to 180cm in stature (without a slight reduction for his lower cranial height) and 80kg in body mass as an adult. Other evidence from the East African Early Pleistocene indicates that KNM-WT 15000 was not unusually large-bodied for his time period.
AB - Because of its completeness, the juvenile Homo ergaster/erectus KNM-WT 15000 has played an important role in studies of the evolution of body form in Homo. Early attempts to estimate his adult body size used modern human growth models. However, more recent evidence, particularly from the dentition, suggests that he may have had a more chimpanzee-like growth trajectory. Here we re-estimate his adult stature and body mass using ontogenetic data derived from four African ape taxa: Pan troglodytes troglodytes, Pan troglodytes schweinfurthii, Pan paniscus, and Gorilla gorilla gorilla. The average percentage change in femoral and tibial lengths and femoral head breadth between individuals at the same stage of dental development as KNM-WT 15000 - eruption of M2s but not M3s - and adult individuals with fully fused long bone epiphyses, was determined. Results were then applied to KNM-WT 15000, and his adult size estimated from skeletal dimensions using modern human prediction formulae. Using this approach, adult stature best estimates of 176-180cm and body mass best estimates of 80-83kg were obtained. These estimates are close to those estimated directly from longitudinal changes in body length and body mass between 8 and 12 years of age in chimpanzees, the suggested chronological equivalent to KNM-WT 15000's remaining growth period. Thus, even using an African ape growth model, it is likely that KNM-WT 15000 would have attained close to 180cm in stature (without a slight reduction for his lower cranial height) and 80kg in body mass as an adult. Other evidence from the East African Early Pleistocene indicates that KNM-WT 15000 was not unusually large-bodied for his time period.
KW - Body mass
KW - Chimpanzee
KW - Gorilla
KW - Homo erectus
KW - Nariokotome boy
KW - Stature
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U2 - 10.1016/j.jhevol.2014.09.005
DO - 10.1016/j.jhevol.2014.09.005
M3 - Article
C2 - 25449954
AN - SCOPUS:84923624219
SN - 0047-2484
VL - 80
SP - 74
EP - 82
JO - Journal of Human Evolution
JF - Journal of Human Evolution
ER -