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El terópodo dromaeosaurídeo más antiguo de América del Sur
Peter J Makovicky1, Sebastián Apesteguía, Federico L Agnolín
1Department of Geology, The Field Museum, 1400 South Lake Shore Drive, Chicago, Illinois 60605, USA.
Nature
|October 14, 2005
Resumen
Los primeros dinosaurios maniraptoranos, incluidos los dromaeosaurios, pueden haberse originado en Gondwana. Un nuevo fósil sudamericano proporciona evidencia de un linaje único de Gondwana anterior a la separación continental.
Área de la Ciencia:
- Paleontología Paleontología.
- Biología evolutiva Biología evolutiva.
- La paleontología de los dinosaurios.
Sus antecedentes:
- La historia evolutiva de Maniraptora (aves y dinosaurios con garras de hoz) se conoce principalmente en el hemisferio norte.
- Los fósiles anteriores de maniraptoran de Gondwana son incompletos y sus afinidades son debatidas.
Objetivo del estudio:
- Para describir un nuevo y bien conservado dinosaurio dromeosáurido de América del Sur.
- Para investigar la evolución temprana y la distribución en Gondwana de los Maniraptora.
- Para proporcionar evidencia de un linaje de Gondwana anterior a la separación continental.
Principales métodos:
- Descripción de un espécimen fósil casi completo.
- Análisis filogenético para determinar las relaciones evolutivas.
- Evaluación paleobiogeográfica de la distribución de los dromaeosaurios.
Principales resultados:
- Descubrimiento del Maniraptora sudamericano más completo y más antiguo.
- Identificación de un linaje único de dromeosaurios de Gondwana.
- La evidencia sugiere que este linaje se originó antes de la ruptura del supercontinente Pangea.
Conclusiones:
- Este descubrimiento desafía la comprensión previa de la distribución de los Maniraptora.
- Apoya la existencia de linajes de dromaeosaurios de Gondwana con orígenes antiguos.
- Los hallazgos tienen implicaciones significativas para reconstruir la evolución de los dinosaurios y la biogeografía.
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