The postcranial skeletal maturation of Australopithecus sediba
Noel Cameron1,2, Barry Bogin1,2, Debra Bolter2,3
1Centre for Global Health and Human Development, School of Sport, Exercise and Health Sciences, Loughborough University, LE11 3TU, United Kingdom.
American Journal of Physical Anthropology
|May 3, 2017
Summary
Australopithecus sediba shows an ape-like skeletal maturity pattern, differing from modern humans. This suggests a recent evolution in human growth and life history strategies.
Area of Science:
- Paleoanthropology
- Human Evolution Studies
- Skeletal Biology
Background:
- Discovery of Australopithecus sediba (Au. sediba) holotype MH1 in South Africa.
- MH1 provides substantial post-cranial remains for skeletal maturation assessment.
- Malapa site dated to 1.9 million years ago.
Purpose of the Study:
- To assess the skeletal maturity of Au. sediba (MH1).
- To compare Au. sediba's maturation pattern with modern humans and chimpanzees.
- To infer potential differences in hominin maturation schedules.
Main Methods:
- Analysis of skeletal maturity indicators on multiple bones of MH1.
- Comparison of indicators with modern human and chimpanzee (Pan troglodytes) reference data.
- Estimation of skeletal maturational age based on these indicators.
Main Results:
- Au. sediba's skeletal age estimated at 12.0–15.0 years compared to humans (mean 13.1 years).
- Au. sediba's skeletal age estimated at 9–11 years compared to chimpanzees.
- Predicted adult height for MH1: 150–156 cm.
Conclusions:
- Au. sediba exhibits an ape-like maturity schedule, consistent with dental age.
- This pattern aligns with Homo erectus (KMN-WT 15000) postcranial immaturity.
- Humans may possess distinct, delayed post-cranial maturation, indicating recent evolutionary changes.
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