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Paleopediatrics: or when did human infants really become human?
1Department of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, MO 63110, USA.
American Journal of Physical Anthropology
|October 1, 1995
Summary
Human children mature slowly compared to chimpanzees. This study finds no link between early human "delayed maturation" and tool-making, challenging previous evolutionary explanations.
Area of Science:
- Paleoanthropology
- Evolutionary Biology
- Primatology
Background:
- Modern human children exhibit delayed maturation compared to chimpanzees.
- Delayed maturation is often hypothesized to facilitate learning complex skills, such as tool-making.
Purpose of the Study:
- To investigate the association between delayed maturation and tool-making abilities in early human evolution.
- To re-evaluate the selective pressures driving the evolution of prolonged childhood dependency.
Main Methods:
- Comparison of dental maturational profiles of early South African hominids with extant humans and chimpanzees.
- Analysis of evidence for tool-making in early hominid fossils.
Main Results:
- No evidence found linking delayed maturation with tool-making abilities in early human evolution.
- The assumed association between prolonged childhood and behaviors like cooperative hunting is questioned.
Conclusions:
- The standard explanation for the evolution of delayed maturation based on tool-making is not supported by early hominid evidence.
- Alternative or additional selective pressures, potentially postdating the australopithecine radiation, likely drove the evolution of delayed maturation.
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