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Un esqueleto completo de un saurísquio del Triásico tardío y la evolución temprana de los dinosaurios
Sterling J Nesbitt1, Nathan D Smith, Randall B Irmis
1Division of Paleontology, American Museum of Natural History, New York, NY 10024, USA. nesbitt@jsg.utexas.edu
Science (New York, N.Y.)
|December 17, 2009
Resumen
Un nuevo fósil de dinosaurio de Nuevo México revela la evolución temprana de los terópodos y las características de las aves. Este hallazgo aclara la diversificación de los dinosaurios y sugiere una dispersión intercontinental generalizada durante el Triásico tardío.
Área de la Ciencia:
- Paleontología Paleontología.
- Biología evolutiva Biología evolutiva.
- Zoología de los vertebrados Zoología de los vertebrados.
Sus antecedentes:
- Comprender la evolución temprana de los dinosaurios es clave para su diversificación en el Triásico Tardío.
- Los fósiles de los linajes basales de dinosaurios son escasos, lo que limita nuestro conocimiento.
Objetivo del estudio:
- Para caracterizar la historia evolutiva de los primeros dinosaurios terópodos.
- Para investigar la diversificación temprana de los dinosaurios en América del Norte.
- Proporcionar información sobre la antigüedad de los sistemas de carácter aviar.
Principales métodos:
- Excavación y análisis de varios esqueletos casi completos de un nuevo dinosaurio terópodo de Nuevo México.
- Estudio anatómico comparativo centrado en las características plesiomorfas y derivadas.
- Análisis paleobiogeográfico de los conjuntos de saurisquios del Triásico tardío.
Principales resultados:
- El nuevo taxón exhibe un mosaico de características primitivas y avanzadas, aclarando la evolución temprana de los saurísquios.
- Se encontraron evidencias de la presencia temprana de pneumaticidad esquelética, una característica clave de las aves.
- El estudio reveló diferencias latitudinales en los conjuntos de saurisquios del Triásico Tardío.
Conclusiones:
- El dinosaurio terópodo descubierto proporciona información crucial sobre la evolución y diversificación de los primeros dinosaurios.
- Los hallazgos sugieren que la fauna de terópodos de América del Norte del Triásico tardío no era endémica, lo que indica una dispersión intercontinental prevalente.
- Esta investigación pone de relieve la antigüedad de las características esqueléticas de las aves en los primeros terópodos.
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