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Published on: March 7, 2016
La química del agua de mar y la temprana biomineralización del carbonato
1Department of Earth Science, University of California at Santa Barbara, Santa Barbara, CA 93106, USA. porter@geol.ucsb.edu
Science (New York, N.Y.)
|June 2, 2007
Resumen
La mineralogía de los esqueletos animales, como la aragonita y la calcita, fue determinada por la química del agua de mar cuando evolucionaron por primera vez. Una vez establecidas, estas mineralogías rara vez cambiaban, incluso cuando las condiciones del océano cambiaban.
Área de la Ciencia:
- Paleontología Paleontología.
- La geoquímica es la geoquímica.
- Biología evolutiva Biología evolutiva.
Sus antecedentes:
- La evolución de la biomineralización en los animales es un evento clave en la historia temprana de los animales.
- Comprender los factores ambientales que influyeron en la elección de los minerales esqueléticos es crucial.
Objetivo del estudio:
- Para investigar la relación entre la química del agua de mar y la mineralogía inicial de esqueletos de animales.
- Determinar si la química del agua de mar en el momento de la evolución del esqueleto influyó en las tendencias mineralógicas a largo plazo.
Principales métodos:
- Análisis de los registros fósiles desde el Ediacaran tardío hasta los períodos Ordoviciano.
- Correlación de la primera aparición de esqueletos de aragonita y calcita en 18 grupos de animales con datos conocidos de química del agua de mar de los mismos intervalos.
Principales resultados:
- La precipitación inicial de esqueletos de aragonita y calcita en distintos grupos de animales coincidió con períodos de química favorable del agua de mar para cada mineral.
- La mineralogía esquelética se mantuvo estable dentro de los clados después de la evolución inicial, independientemente de las fluctuaciones químicas posteriores del agua de mar.
Conclusiones:
- La química del agua de mar en el momento del origen esquelético fue el principal determinante de la mineralogía esquelética en la evolución animal temprana.
- Esta temprana influencia ambiental estableció vías minerológicas que persistieron a través de los cambios geológicos posteriores.
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