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Desacoplados patrones temporales de evolución y ecología en dos clades post-paleozoicos
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
Resumen
El éxito evolutivo y el dominio ecológico pueden diferir significativamente durante millones de años. Los recuentos de diversidad taxonómica por sí solos no capturan completamente la importancia ecológica de los grupos de bryozoos como Cyclostomata y Cheilostomata.
Área de la Ciencia:
- Paleontología Paleontología.
- Biología evolutiva Biología evolutiva.
- Ecología marina Ecología marina.
Sus antecedentes:
- Los recuentos de diversidad taxonómica son estándar para el seguimiento de patrones macroevolutivos en el registro fósil.
- Los bryozoos, en particular los ciclostomatos y los chelostomatos, son importantes invertebrados marinos con distintas historias evolutivas.
- Estudios anteriores a menudo se basan en métricas de diversidad, potencialmente pasando por alto la dinámica ecológica.
Objetivo del estudio:
- Investigar los patrones seculares de importancia ecológica relativa entre los ciclostomatos y los chelostomatos.
- Para determinar si las métricas estándar de diversidad reflejan con precisión el dominio ecológico en los bryozoos fósiles.
- Para evaluar la recuperación ecológica de Cheilostomata después de la extinción masiva del Cretácico-Terciario.
Principales métodos:
- Análisis de la ocurrencia de bryozoos fósiles y datos de diversidad en escalas de tiempo geológicas.
- Comparación de la diversidad genérica y la riqueza de especies dentro de la fauna con métricas de importancia ecológica.
- Examen de los cambios en la composición de clado a través de la frontera Cretácico-Terciario.
Principales resultados:
- Las métricas genéricas de diversidad y riqueza de especies no representan completamente la importancia ecológica de Cyclostomata y Cheilostomata.
- La recuperación ecológica tardía de Cheilostomata después del evento de extinción del Cretácico-Terciario no es evidente en las compilaciones de diversidad.
- Se observa una disociación entre el éxito evolutivo (diversidad) y el dominio ecológico durante millones de años.
Conclusiones:
- Los recuentos estándar de diversidad son insuficientes para comprender completamente la dinámica ecológica macroevolucionaria.
- El éxito evolutivo y el dominio ecológico pueden ser distintos y asincrónicos, incluso durante períodos prolongados.
- Es necesario repensar las métricas para evaluar los patrones evolutivos y ecológicos en el registro fósil.
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