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Size of the permo-triassic bottleneck and its evolutionary implications
Science (New York, N.Y.)
|October 12, 1979
Summary
The Late Permian extinction wiped out 96% of marine species, creating a severe bottleneck. This event likely caused random species loss and shaped future marine life through an evolutionary founder effect.
Area of Science:
- Paleontology
- Marine Biology
- Evolutionary Biology
Background:
- The Late Permian period witnessed a catastrophic mass extinction event.
- This event significantly impacted marine ecosystems, leading to a drastic reduction in biodiversity.
Purpose of the Study:
- To analyze the severity of the Late Permian extinction using rarefaction analysis.
- To investigate the potential impact of this extinction on marine species composition and evolution.
Main Methods:
- Rarefaction analysis was employed to estimate extinction percentages.
- Biological composition changes across the Permo-Triassic boundary were examined.
Main Results:
- Rarefaction analysis suggests up to 96% of marine species may have gone extinct.
- The marine biosphere experienced a significant bottleneck event.
- Observed changes in species composition at the Permo-Triassic boundary are consistent with an evolutionary founder effect.
Conclusions:
- The Late Permian extinction was exceptionally severe, drastically reducing marine biodiversity.
- The extinction likely involved the chance elimination of various biological groups.
- An evolutionary founder effect following the bottleneck is a probable explanation for post-extinction species composition.
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