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Los efectos del cambio global del Cenozoico en la filogenia de las ardillas
1Biology Department, Duke University, Durham, NC 27708-0338, USA. jmercer@duke.edu
Science (New York, N.Y.)
|February 22, 2003
Resumen
El clima global y los cambios tectónicos influyeron significativamente en la diversificación de las antiguas familias de ardillas (Sciuridae) en los continentes. Estos eventos geológicos dieron forma a la historia evolutiva y la propagación geográfica de las ardillas en todo el mundo.
Área de la Ciencia:
- Biología evolutiva Biología evolutiva.
- Paleontología Paleontología.
- La mammalogía es la mamalogía.
Sus antecedentes:
- El cambio climático y los eventos tectónicos tienen un impacto significativo en la diversificación de los organismos terrestres.
- Estos efectos son más pronunciados en grupos filogenéticos antiguos, extendidos y diversos.
- La familia de las ardillas (Sciuridae) es un grupo de mamíferos distribuidos globalmente, ideal para estudiar estos procesos evolutivos.
Objetivo del estudio:
- Investigar el papel del cambio global en la diversificación de la familia de las ardillas (Sciuridae).
- Para correlacionar la historia evolutiva de las ardillas con eventos geológicos y de nivel del mar documentados.
Principales métodos:
- Se realizaron análisis filogenéticos en la familia de las ardillas.
- Se emplearon análisis de reloj molecular para estimar los tiempos de divergencia.
- El momento y la ubicación de la diversificación de las ardillas se compararon con eventos geológicos conocidos.
Principales resultados:
- La llegada y diversificación de las ardillas a África, las islas de la Plataforma Sunda, Beringia y el istmo panameño coincidieron con importantes eventos geológicos.
- Estos eventos incluyeron cambios documentados en el nivel del mar, actividad tectónica y eventos paleontológicos.
- Se observaron correlaciones temporales y espaciales precisas entre la evolución de las ardillas y el cambio global.
Conclusiones:
- El cambio global, que abarca el clima y los cambios tectónicos, jugó un papel crucial en la diversificación de las ardillas.
- La historia evolutiva de los Sciuridae proporciona un claro ejemplo de cómo los eventos geológicos dan forma a la diversidad de los mamíferos.
- Este estudio pone de relieve la interconexión de los procesos geológicos y las trayectorias evolutivas en los mamíferos terrestres.
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