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Un nuevo orden de zalambdodont marsupiales terciarios
Science (New York, N.Y.)
|March 25, 1988
Resumen
Dos nuevas especies de marsupiales, Yalkaparidon coheni y Yalkaparidon jonesi, revelan una familia y un orden previamente desconocidos. Su descubrimiento en la Australia Terciaria destaca una mayor diversidad de marsupiales y convergencia evolutiva.
Área de la Ciencia:
- Paleontología Paleontología.
- Zoología Zoología Zoología.
- Biología evolutiva Biología evolutiva.
Sus antecedentes:
- La radiación del marsupial australiano incluye cinco órdenes conocidas de Australidelphia.
- Los marsupiales zalambdodont poseen patrones de cúspide molar altamente especializados.
- Los descubrimientos de fósiles terciarios son cruciales para comprender la historia evolutiva de los mamíferos de Australia.
Objetivo del estudio:
- Para describir dos nuevas especies, Yalkaparidon coheni y Yalkaparidon jonesi.
- Establecer la nueva familia de marsupiales Yalkaparidontidae y el orden Yalkaparidontia.
- Para investigar las relaciones evolutivas y la paleoecología de estos marsupiales recién descubiertos.
Principales métodos:
- Excavación y recuperación de fósiles de sedimentos del Terciario en el noroeste de Queensland.
- Análisis morfológico detallado de las características dentales y craneales básicas.
- Análisis comparativo con taxones de marsupiales existentes y extintos.
Principales resultados:
- Yalkaparidon coheni y Yalkaparidon jonesi se describen como los primeros miembros de Yalkaparidontidae y Yalkaparidontia.
- Yalkaparidontids exhiben molares zalambdodont, lo que sugiere una convergencia dental con los notoryctids.
- La evidencia fósil indica que los yalkaparidontids habitaron las selvas tropicales de tierras bajas durante el Terciario medio a tardío.
Conclusiones:
- El descubrimiento de Yalkaparidontidae expande significativamente la diversidad conocida de los marsupiales australianos.
- Los yalkaparidontidos probablemente coexistieron y desaparecieron junto con los ecosistemas de las selvas tropicales terciarias.
- La morfología dental indica una evolución convergente en los marsupiales zalambdodont, lo que desafía las suposiciones filogenéticas anteriores.
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