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Two-step Approach to Explore Early- and Late-stages of Organ Formation in the Avian Model: The Thymus and Parathyroid Glands Organogenesis Paradigm
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Histología ósea. Evolución del patrón de crecimiento en las aves
1Department of Zoology, University of Cape Town, Private Bag, Rondebosch 7700, South Africa.
Nature
|July 27, 2001
Resumen
Las aves modernas crecen rápidamente y vuelan después de alcanzar su tamaño completo. Sin embargo, la evolución temprana de las aves puede haber involucrado voladores precoces, como lo indican las ralentizaciones tempranas del crecimiento en los linajes de aves basales.
Área de la Ciencia:
- Paleontología Paleontología.
- Biología evolutiva Biología evolutiva.
- Zoología de los vertebrados Zoología de los vertebrados.
Sus antecedentes:
- Las aves vivas (neornitinas) exhiben un crecimiento rápido e ininterrumpido, que generalmente se completa en un año y alcanza el vuelo cerca de su plena madurez.
- La histología ósea en los terópodos pre-aviares indica un crecimiento postnatal rápido, pero a menudo intermitente, que se extiende más allá de un año.
Objetivo del estudio:
- Para investigar los patrones de crecimiento en los primeros linajes aviares.
- Comparar las estrategias de crecimiento de las aves basales con las de las aves modernas y los terópodos no aviares.
- Para inferir la trayectoria evolutiva de la adquisición de vuelo en las aves primitivas.
Principales métodos:
- Análisis de la histología ósea de especímenes fósiles de dos linajes de aves basales voladoras.
- Análisis comparativo de los patrones de crecimiento en diferentes grupos de aves y terópodos.
Principales resultados:
- Descubrimiento de una desaceleración temprana del crecimiento postnatal en dos linajes de aves basales voladoras.
- Este patrón contrasta con el continuo y rápido crecimiento de las aves modernas y el crecimiento intermitente de los terópodos no aviares.
Conclusiones:
- El patrón de crecimiento observado sugiere que las aves primitivas pueden haber desarrollado la capacidad de vuelo más temprano en su desarrollo.
- Esto indica un potencial para capacidades de vuelo precoz en la historia evolutiva de las aves.
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