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Published on: May 12, 2019
Una rana del Eoceno superior de la República Dominicana y su implicación para la biogeografía caribeña
Resumen
El descubrimiento de fósiles de ranas en ámbar del Eoceno revela la antigua fauna de las Antillas, anterior al conocimiento actual. Este fósil de lisanfibio completo más antiguo de Mesoamérica destaca los movimientos de las masas terrestres del Terciario.
Área de la Ciencia:
- Paleontología Paleontología.
- Zoología de los vertebrados Zoología de los vertebrados.
- La paleobiogeografía es la paleobiogeografía.
Sus antecedentes:
- Los fósiles de anfibios proporcionan información crucial sobre la historia evolutiva y los ecosistemas del pasado.
- Las inclusiones de ámbar preservan estructuras biológicas delicadas, ofreciendo ventanas únicas a la vida antigua.
- El registro fósil de Mesoamérica, particularmente de la época del Eoceno, es escaso.
Objetivo del estudio:
- Para describir un fósil de rana recién descubierto conservado en ámbar dominicano del Eoceno.
- Para establecer el registro fósil de lisanfibios completo más antiguo de Mesoamérica.
- Inferir la composición de la fauna de las Antillas durante el Eoceno y sus implicaciones biogeográficas.
Principales métodos:
- Datación geológica de la matriz de ámbar para determinar su edad en el Eoceno.
- Análisis morfológico detallado del fósil de anfibio conservado.
- Osteología comparativa y ubicación filogenética del fósil dentro del género Eleutherodactylus.
Principales resultados:
- Identificación de una rana leptodactílida, género Eleutherodactylus, dentro del ámbar del Eoceno.
- Esto representa el primer fósil de anfibio encontrado en ámbar y el lissamphibian completo más antiguo de Mesoamérica.
- La datación del ámbar indica que una diversa fauna de las Antillas existía a finales del Eoceno, antes de lo que se pensaba.
Conclusiones:
- El descubrimiento retrasa la línea de tiempo conocida para la diversa vida anfibia en las Antillas.
- Este fósil, junto con otros hallazgos de ámbar, sugiere que los movimientos de las masas terrestres terciarias moldearon significativamente la distribución actual de las especies.
- Los hallazgos subrayan la importancia de los fósiles de ámbar en la reconstrucción de la paleobiogeografía neotropical.
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