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Los bryozoos más antiguos: nueva evidencia del Ordoviciano temprano
Science (New York, N.Y.)
|May 19, 1978
Resumen
Un fósil abundante de la piedra caliza de la Roca Negra del Ordovícico Inferior se identifica como un bryozoario dianulitido no descrito. Este descubrimiento representa el más antiguo bryozoan conocido, con un crecimiento variado influenciado por el medio ambiente.
Área de la Ciencia:
- Paleontología Paleontología.
- Biología Marina Biología Marina.
- Geología Geología Geología.
Sus antecedentes:
- La piedra caliza Black Rock del Ordovícico Inferior (canadiense) del área de Ozark Uplift contiene fósiles abundantes, pero problemáticos.
- Los bryozoos son invertebrados marinos coloniales con un registro fósil significativo.
Objetivo del estudio:
- Identificar y describir un fósil abundante y problemático de la piedra caliza de la Roca Negra del Ordovícico Inferior.
- Para establecer el registro fósil más antiguo e incuestionable de los bryozoos.
- Para investigar la morfología del crecimiento y las influencias ambientales en este bryozoan temprano.
Principales métodos:
- Recopilación y análisis de fósiles de la zona del Ozark Uplift.
- Examen morfológico del dianulitídeo no descrito bryozoan.
- Evaluación estratigráfica y paleoambiental.
Principales resultados:
- Identificación de un bryozoan dianulitid no descrito como el fósil abundante y problemático.
- Este espécimen es considerado el más antiguo bryozoan incuestionable conocido.
- Se observó una variación significativa en la morfología del crecimiento, lo que sugiere la influencia ambiental.
Conclusiones:
- El bryozoan dianulitid recientemente descrito representa la evidencia definitiva más antigua de este filo.
- Los factores ambientales jugaron un papel crucial en la configuración de la morfología de los primeros briozoos.
- Este hallazgo mejora nuestra comprensión de los ecosistemas marinos del Ordovícico y la evolución de los bryozoos.
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