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Tendencias ambientales en la extinción durante el Paleozoico
1Department of the Geophysical Sciences, University of Chicago, IL 60637, USA.
Science (New York, N.Y.)
|January 2, 1987
Resumen
Las comunidades marinas del Paleozoico muestran una mayor extinción en alta mar, mientras que la extinción de géneros individuales es mayor en tierra. Este patrón refleja la estabilidad ambiental que influye en las tasas de extinción en diferentes taxones.
Área de la Ciencia:
- Paleontología Paleontología.
- Ecología marina Ecología marina.
- La estratigrafía es la estratigrafía.
Sus antecedentes:
- Los patrones de extinción son cruciales para comprender la dinámica y la evolución de las comunidades marinas.
- Los factores ambientales, como la proximidad a la costa, pueden influir significativamente en la supervivencia de las especies.
- Estudios anteriores sugieren diferentes sensibilidades a la extinción entre los diferentes grupos taxonómicos.
Objetivo del estudio:
- Para investigar los patrones de intensidad de extinción en los conjuntos marinos del Paleozoico a través de gradientes ambientales.
- Para determinar si las tendencias de extinción a nivel comunitario difieren de las de las clases taxonómicas individuales.
- Para correlacionar los patrones de extinción con la previsibilidad y estabilidad ambiental.
Principales métodos:
- Análisis de las intensidades de extinción de 505 conjuntos de fósiles marinos del Paleozoico.
- Clasificación de los conjuntos en seis zonas ambientales distintas y 40 intervalos estratigráficos.
- Comparación de las tasas de extinción tanto a nivel de comunidad como a nivel de clase taxonómica.
Principales resultados:
- Comunidades marinas enteras exhibieron una tasa de extinción creciente al moverse hacia la costa.
- Las generaciones dentro de las clases taxonómicas individuales mostraron tasas de extinción más altas en entornos cercanos a la costa.
- La tendencia observada a nivel comunitario se atribuye a la distribución de taxones con tasas de extinción más bajas en las zonas cercanas a la costa.
Conclusiones:
- La estabilidad ambiental juega un papel clave en las dinámicas de extinción marina.
- Los organismos en entornos predeciblemente estables (offshore) experimentaron una extinción más baja que aquellos en entornos fluctuantes cercanos a la costa.
- Los patrones de extinción son dependientes de la escala, y difieren entre comunidades enteras y grupos taxonómicos individuales.
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