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El desarrollo de la pelvis de las aves pasa por condiciones ancestrales de los dinosaurios
Christopher T Griffin1,2,3, João F Botelho1,2,4, Michael Hanson1,2
1Department of Earth and Planetary Sciences, Yale University, New Haven, CT, USA.
Nature
|July 27, 2022
Resumen
El desarrollo de la pelvis de las aves revela rasgos ancestrales de los dinosaurios que aparecen transitoriamente durante el crecimiento embrionario. Este patrón evolutivo sugiere un mecanismo de "adición terminal" en la evolución de las aves.
Área de la Ciencia:
- Paleontología
- Biología del desarrollo
- Biología evolutiva
Sus antecedentes:
- Las aves vivas (Aves) exhiben modificaciones anatómicas significativas de sus antepasados reptiles.
- La pelvis aviar sufrió cambios sustanciales durante la transición de los primeros arcosaurios a las aves modernas.
- Si bien el registro fósil documenta los cambios evolutivos, los procesos de desarrollo subyacentes (ontogenia) son menos comprendidos.
Objetivo del estudio:
- Investigar la morfogénesis tridimensional de los tejidos pélvicos aviares mediante imágenes embriológicas.
- Para comparar el desarrollo pélvico de las aves con el registro fósil de las transiciones de dinosaurios a aves.
- Comprender las bases del desarrollo de la pelvis aviar.
Principales métodos:
- Utilizó técnicas avanzadas de imágenes embriológicas para examinar el desarrollo del tejido pélvico en tres dimensiones.
- Se han realizado análisis cuantitativos para comparar la ontogenia pélvica aviar con las secuencias filogenéticas.
- Investigó la covarianza fenotípica dentro de la pelvis a través de los archosaurios.
Principales resultados:
- Las características pélvicas ancestrales de los dinosaurios (por ejemplo, el pubis orientado hacia adelante, la "botina" púbica) se observan transitoriamente durante la embriogénesis temprana de las aves.
- El desarrollo pélvico aviar sigue una secuencia prenatal que refleja la adquisición evolutiva de rasgos de los dinosaurios no aviares.
- Se ha demostrado la covarianza fenotípica en la pelvis, conservada a través de los archosaurios, lo que podría explicar la retención de los estados ancestrales.
Conclusiones:
- La evolución pélvica aviar probablemente ocurrió a través de la "adición terminal", donde se agregan nuevos rasgos al final de una secuencia de desarrollo, expresando estados ancestrales anteriores.
- La integración fenotípica en la pelvis sugiere un nuevo mecanismo para la adición terminal durante la evolución.
- El estudio destaca la importancia de estudiar el desarrollo embrionario para comprender las transiciones evolutivas y la retención de los rasgos ancestrales.
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