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Evolución de los primeros animales: puntos de vista emergentes de la biología y la geología comparativas
1Department of Organismic and Evolutionary Biology, Harvard University, 26 Oxford Street, Cambridge, MA 02138, USA.
Science (New York, N.Y.)
|June 26, 1999
Resumen
La evolución temprana de los animales involucró el ensamblaje de herramientas genéticas del Proterozoico y la diversificación del Cámbrico. Los cambios ambientales y las interacciones ecológicas probablemente desencadenaron y amplificaron este evento de radiación del Cámbrico.
Área de la Ciencia:
- Biología evolutiva Biología evolutiva.
- Paleontología Paleontología.
- Biología del desarrollo Biología del desarrollo.
Sus antecedentes:
- La explosión cámbrica, marcada por la rápida aparición de diversos grupos de animales, ha desconcertado durante mucho tiempo a los científicos con respecto a sus impulsores evolutivos.
- Investigaciones anteriores se centraron en hipótesis sobre catalizadores genéticos o ambientales para la evolución animal temprana.
Objetivo del estudio:
- Para resolver la secuencia de factores genéticos, morfológicos, ambientales y ecológicos que dan forma a la evolución animal temprana.
- Comprender la interacción entre el ensamblaje del conjunto de herramientas genéticas, la diversificación morfológica y los cambios ambientales durante los períodos Proterozoico y Cámbrico.
Principales métodos:
- Análisis de los registros fósiles para comprender las innovaciones morfológicas.
- Investigación de datos genéticos para rastrear el ensamblaje de kits de herramientas de desarrollo.
- Reconstrucción de eventos ambientales e interacciones ecológicas durante la transición Proterozoico-Cámbrico.
Principales resultados:
- El conjunto de herramientas genéticas modernas para el desarrollo se ensambló durante el Eón Proterozoico.
- Los principales grupos de animales divergieron inicialmente durante el Proterozoico.
- Las morfologías del grupo de la corona se diversificaron en el Cámbrico a través de alteraciones en las redes de regulación genética que rigen el desarrollo animal.
Conclusiones:
- La evolución del Cámbrico fue moldeada por una combinación de innovaciones genéticas del Proterozoico y factores ambientales y ecológicos del Cámbrico.
- Las perturbaciones ambientales cerca de la frontera entre el Proterozoico y el Cámbrico pueden haber iniciado la radiación del Cámbrico.
- Las interacciones ecológicas dentro de los ecosistemas en evolución probablemente amplificaron el evento de radiación del Cámbrico.
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