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Huellas fósiles parecidas a pájaros del Triásico tardío
Ricardo N Melchor1, Silvina De Valais, Jorge F Genise
1CONICET and Universidad Nacional de La Pampa, Av. Uruguay 151, 6300 Santa Rosa, La Pampa, Argentina. melchor_r@cpsarg.com
Nature
|June 28, 2002
Resumen
Las huellas de dinosaurios de Argentina.
Área de la Ciencia:
- Paleontología Paleontología.
- Paleontología de los Vertebrados.
- Es la tecnología.
Sus antecedentes:
- El registro fósil de las aves comienza en el Jurásico Tardío con Archaeopteryx.
- Los antepasados de las aves (coelurosaurios) se remontan al Jurásico Temprano.
- Los terópodos del Triásico tardío carecen de evidencia esquelética de características aviares como un hallux invertido.
Objetivo del estudio:
- Para describir nuevas huellas fósiles con características aviares.
- Investigar el origen y la evolución de las aves a través de la ichnología.
- Desafiar las líneas de tiempo existentes para la evolución de las aves.
Principales métodos:
- Análisis de huellas fósiles bien conservadas de los lechos rojos del Triásico tardío en Argentina.
- Análisis icnológico comparativo para identificar las características de las aves.
- Reconstrucción paleoambiental del entorno de deposición.
Principales resultados:
- Descubrimiento de abundantes huellas exhibiendo claros caracteres aviares.
- Estas huellas son anteriores a los primeros fósiles esqueléticos de aves conocidos por al menos 55 millones de años.
- Las huellas sugieren la presencia de terópodos con rasgos aviares en el Triásico Tardío.
Conclusiones:
- Los hallazgos retrasan el origen conocido de los caracteres aviares en los terópodos hasta el Triásico Tardío.
- La icnología proporciona evidencia crucial para la comprensión de la evolución de las aves.
- Estas huellas representan un grupo desconocido de terópodos con afinidades aviares tempranas.
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