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Published on: September 3, 2009
The accretion model of Neandertal evolution.
1Department of Anthropology, University of Utah, Salt Lake City 84112-0060, USA. john.hawks@anthro.utah.edu
Evolution; International Journal of Organic Evolution
|August 30, 2001
Summary
The Accretion model suggests Neandertals evolved in isolation, but fossil data shows European populations were not significantly different from contemporaries. This challenges the isolation hypothesis for Neandertal evolution.
Area of Science:
- Paleoanthropology
- Human Evolution
- Pleistocene Studies
Background:
- The Accretion model posits Neandertal evolution in Europe resulted from genetic isolation and trait accumulation.
- This model suggests reduced genetic variability in European populations due to genetic drift and limited gene flow.
Purpose of the Study:
- To test the Accretion model of Neandertal evolution using fossil data from the Middle and Late Pleistocene.
- To evaluate the degree of genetic isolation and divergence of European hominin populations.
Main Methods:
- Analysis of fossil data from European Middle and Late Pleistocene hominin populations.
- Comparison of morphological traits to assess divergence from contemporary human populations.
- Testing evolutionary patterns against predictions of the Accretion model.
Main Results:
- European populations did not show significant divergence from contemporary populations.
- A subset of traits, chosen for maximum potential difference, also showed no significant divergence.
- The pattern of trait changes over time in Europe did not support the Accretion model's predictions.
Conclusions:
- The Accretion model is not supported by the fossil evidence.
- Near-complete isolation of European populations during the Pleistocene is not necessary to explain evolutionary patterns.
- Gene flow between regions is a more plausible explanation for hominin evolution in Europe.
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