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Presencia del tejido duro de los vertebrados más antiguos en los conodontes
I J Sansom1, M P Smith, H A Armstrong
1Department of Geological Sciences, University of Durham, United Kingdom.
Science (New York, N.Y.)
|May 29, 1992
Resumen
El análisis histológico revela tejidos esqueléticos de vertebrados en elementos conodontes, lo que confirma sus afinidades con los vertebrados. Este descubrimiento retrasa el origen de los tejidos duros de los vertebrados en 40 millones de años hasta el Cámbrico Tardío.
Área de la Ciencia:
- Paleontología Paleontología.
- Biología de los vertebrados Biología de los vertebrados.
- Histología Histología Histología.
Sus antecedentes:
- Los elementos del conodonte son estructuras fosilizadas de afinidad desconocida.
- Investigaciones anteriores han debatido la posición filogenética de los conodontes.
Objetivo del estudio:
- Para investigar la composición microestructural de los elementos de los conodontes.
- Para determinar las afinidades vertebradas de los conodontes a través del análisis de tejidos.
Principales métodos:
- Examen histológico de las microestructuras de los elementos conodontes.
- Identificación de los tejidos esqueléticos característicos de los vertebrados.
Principales resultados:
- Los elementos del conodonte contienen hueso celular, homólogos hipermineralizados del esmalte y cartílago calcificado globular.
- La presencia de hueso celular proporciona evidencia definitiva de las afinidades de los vertebrados.
- Los tejidos duros de los vertebrados se identifican en los conodontes del Cámbrico Tardío (hace 515 millones de años).
Conclusiones:
- Los conodontes se confirman como vertebrados basados en la histología del tejido esquelético.
- La aparición más temprana de tejidos duros de vertebrados ahora se data del Cámbrico Tardío, precediendo a las estimaciones anteriores en 40 millones de años.
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