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Plumas nonavianas en un arcosaurio del Triásico tardío
T D Jones1, J A Ruben, L D Martin
1Department of Zoology, Oregon State University, Corvallis, OR 97331, USA. tdjones@sfasu.edu
Resumen
Longisquama insignis, un arcosaurio del Triásico tardío, poseía estructuras parecidas a plumas que pueden ser homólogas a las plumas de las aves. Estos hallazgos sugieren que las plumas podrían ser anteriores a las aves más antiguas conocidas.
Área de la Ciencia:
- Paleontología Paleontología.
- Biología evolutiva Biología evolutiva.
- Zoología de los vertebrados Zoología de los vertebrados.
Sus antecedentes:
- Longisquama insignis es un archosaurio extinto del Triásico Tardío de Asia central.
- Este dinosaurio poseía apéndices integumentarios emparejados únicos a lo largo de su lado dorsal.
Objetivo del estudio:
- Para analizar la morfología de los apéndices integumentarios de Longisquama.
- Para determinar la homología potencial entre estas estructuras y plumas de aves.
- Para investigar los orígenes evolutivos de las plumas.
Principales métodos:
- Análisis anatómico comparativo de los apéndices de Longisquama.
- Examen de la estructura de la región basal y comparación con la anatomía moderna de las plumas de las aves.
Principales resultados:
- Los apéndices de Longisquama comparten similitudes anatómicas significativas con las plumas de las aves, particularmente en la base.
- Las estructuras basales sugieren procesos de desarrollo similares (morfogénesis) como la pluma aviar calami.
- La posición filogenética exacta de Longisquama en relación con las aves sigue siendo incierta.
Conclusiones:
- Los apéndices integumentarios de Longisquama se interpretan como plumas no aviares.
- Estas estructuras son probablemente homólogas con las plumas de las aves.
- Si son homólogos, estas plumas son anteriores a las de Archaeopteryx, la ave más antigua conocida.
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