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Published on: August 9, 2019
Ontogenia en las colonias animales: una tendencia persistente en el registro fósil de los bryozoos
Resumen
El crecimiento de los bryozoos incrustantes evolucionó significativamente durante más de 100 millones de años, con un modo de crecimiento reemplazando a otro. Esta tendencia evolutiva en los bryozoos chelostomos sugiere una importancia adaptativa en su desarrollo.
Área de la Ciencia:
- Paleontología Paleontología.
- Biología evolutiva Biología evolutiva.
- Biología Marina Biología Marina.
Sus antecedentes:
- Bryozoos encrustantes de cheilostoma exhiben diversos patrones de crecimiento zoóideos y de colonia.
- Comprender la trayectoria evolutiva de estos modos de crecimiento es crucial para comprender la diversificación de los briozoos.
Objetivo del estudio:
- Para investigar la mayor transición evolutiva en los modos de crecimiento de los bryozoos encrustados de cheilostome en los últimos 100 millones de años.
- Identificar tendencias y factores ecológicos que influyen en estos cambios en las faunas fósiles de América del Norte.
Principales métodos:
- Análisis comparativo de especies dentro de sucesivas faunas fósiles de América del Norte.
- Examen de la evidencia ecológica de las faunas bryozoares existentes (vivas).
Principales resultados:
- Se observó una tendencia evolutiva persistente en la que un modo primario de crecimiento de zoóides y colonias fue reemplazado gradualmente por otro.
- La tendencia fue polifilética, lo que indica la evolución independiente de estrategias de crecimiento similares en diferentes linajes.
- Los datos ecológicos de las especies vivas apoyan la importancia adaptativa de esta transición.
Conclusiones:
- La transición evolutiva en los modos de crecimiento entre los queilóstomos encrustados es una tendencia significativa a largo plazo.
- Esta transición parece estar impulsada por presiones adaptativas, como lo demuestran los datos ecológicos y su ocurrencia generalizada en todos los linajes.
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