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Un spinneret devónico: evidencia temprana de arañas y el uso de la seda
Science (New York, N.Y.)
|October 27, 1989
Resumen
Se ha descubierto la evidencia más antigua de la producción de seda de araña, una espineta fosilizada del período devónico. Este hallazgo retrasa el origen de las arañas y la producción de seda en millones de años.
Área de la Ciencia:
- Paleontología Paleontología.
- La aracnología es la aracología.
- Biología evolutiva Biología evolutiva.
Sus antecedentes:
- El registro fósil de las primeras arañas (Araneae) es escaso y a menudo carece de características definitivas.
- Los fósiles devonianos anteriores atribuidos a arañas han sido cuestionados debido a la falta de características clave de las arañas.
Objetivo del estudio:
- Para informar sobre el descubrimiento del fósil de araña más antiguo conocido con estructuras productoras de seda.
- Para determinar la posición filogenética de este antiguo arácnido productor de seda.
Principales métodos:
- Excavación paleontológica y análisis de una espineta fosilizada de rocas del Devónico Medio.
- Análisis morfológico comparativo de las espigotas fosilizadas con subórdenes de arañas existentes.
Principales resultados:
- Un spinneret de araña casi completo, fechado hace 385-380 millones de años, fue descubierto cerca de Gilboa, Nueva York.
- Este fósil representa la evidencia más antigua de la producción de seda a partir de espigotes opisthosomal, lo que confirma su estatus como una araña.
- La morfología de la espigota muestra afinidades tanto con Mesothelae como con Opisthothelae, lo que sugiere una posición basal dentro del clado de la araña.
Conclusiones:
- Este descubrimiento es significativamente anterior a la evidencia previamente aceptada para las arañas y la producción de seda.
- El fósil proporciona información crucial sobre la evolución temprana y la diversificación de las arañas.
- La ubicación filogenética sugiere que puede representar un grupo hermano de todas las otras arañas, Mesothelae u Opisthothelae.
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