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Updated: Jul 24, 2026
08:02
Dissection and Flat-mounting of the Threespine Stickleback Branchial Skeleton
Published on: May 7, 2016
Decoupled temporal patterns of evolution and ecology in two post-Paleozoic clades
F K McKinney1, S Lidgard, J J Sepkoski
1Department of Geology, Appalachian State University, Boone, NC 28608-2067, USA. mckinneyfk@appstate.edu
Science (New York, N.Y.)
|August 7, 1998
Summary
Evolutionary success and ecological dominance can differ significantly over millions of years. Taxonomic diversity counts alone do not fully capture the ecological importance of bryozoan clades like Cyclostomata and Cheilostomata.
Area of Science:
- Paleontology
- Evolutionary Biology
- Marine Ecology
Background:
- Taxonomic diversity counts are standard for tracking macroevolutionary patterns in the fossil record.
- Bryozoans, particularly Cyclostomata and Cheilostomata, are important marine invertebrates with distinct evolutionary histories.
- Previous studies often rely on diversity metrics, potentially overlooking ecological dynamics.
Purpose of the Study:
- To investigate the secular patterns of relative ecological importance between Cyclostomata and Cheilostomata.
- To determine if standard diversity metrics accurately reflect ecological dominance in fossil bryozoans.
- To assess the ecological recovery of Cheilostomata following the Cretaceous-Tertiary mass extinction.
Main Methods:
- Analysis of fossil bryozoan occurrences and diversity data over geological timescales.
- Comparison of generic diversity and within-fauna species richness with ecological importance metrics.
- Examination of clade composition changes across the Cretaceous-Tertiary boundary.
Main Results:
- Generic diversity and species richness metrics do not fully represent the ecological importance of Cyclostomata and Cheilostomata.
- The delayed ecological recovery of Cheilostomata after the Cretaceous-Tertiary extinction event is not evident in diversity compilations.
- A decoupling between evolutionary success (diversity) and ecological dominance is observed over millions of years.
Conclusions:
- Standard diversity counts are insufficient for fully understanding macroevolutionary ecological dynamics.
- Evolutionary success and ecological dominance can be distinct and asynchronous, even over extended periods.
- Rethinking metrics for assessing evolutionary and ecological patterns in the fossil record is necessary.
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