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A kill curve for Phanerozoic marine species
1Department of the Geophysical Sciences, University of Chicago, Illinois 60637, USA.
Paleobiology
|January 1, 1991
Summary
This study analyzes Phanerozoic species extinction patterns, revealing that extinction risk varies significantly over time. Most periods show low extinction rates, punctuated by occasional extinction pulses.
Area of Science:
- Paleontology
- Stratigraphy
- Evolutionary Biology
Background:
- The fossil record provides crucial insights into the history of life on Earth.
- Understanding extinction patterns is key to comprehending evolutionary dynamics.
Purpose of the Study:
- To develop a "kill curve" illustrating extinction risk for Phanerozoic species.
- To analyze extinction rate variations throughout geological time.
Main Methods:
- Analysis of stratigraphic ranges for 17,621 genera, utilizing Sepkoski's compilation.
- Development of a kill curve based on genus-level extinction data.
Main Results:
- The kill curve demonstrates substantial variation in species extinction risk across Phanerozoic time.
- Most geological intervals exhibit very low extinction risks.
- The average extinction rate (0.25/m.y.) is a composite of prolonged low-risk periods and infrequent high-risk pulses.
Conclusions:
- The developed kill curve is a descriptive model of the fossil record's extinction patterns.
- While not directly indicating causes, the kill curve can help constrain hypotheses about extinction mechanisms.
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