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Saccorhytus es un ecdizoario temprano y no el deuterostomo más antiguo
Yunhuan Liu1, Emily Carlisle2, Huaqiao Zhang3
1School of Earth Science and Resources, Chang'an University, Xi'an, China.
Nature
|August 17, 2022
Resumen
Saccorhytus coronarius, que una vez se pensó que era un deuteróstomo temprano, es reclasificado. Un nuevo análisis revela que pertenece a Ecdysozoa, expandiendo nuestra comprensión de la diversidad animal del Cámbrico temprano.
Área de la Ciencia:
- Paleontología
- Biología del desarrollo
- Biología evolutiva
Sus antecedentes:
- Los orígenes evolutivos de los deuteróstomos siguen siendo objeto de debate debido a la falta de representantes tempranos.
- Saccorhytus coronarius fue propuesto anteriormente como un deuterostomo temprano, explicando las discrepancias en la escala de tiempo evolutiva.
Objetivo del estudio:
- Para reevaluar la posición filogenética de Saccorhytus coronarius.
- Para aclarar la historia evolutiva temprana de los deuteróstomos y la fauna cámbrica.
Principales métodos:
- Análisis del nuevo material fósil de Saccorhytus coronarius.
- Reconstrucción de la morfología de S. coronarius.
- Análisis filogenéticos que incorporan nuevos datos morfológicos.
Principales resultados:
- S. coronarius es un animal milimétrico, meiobético con una boca terminal y sin ano.
- Las características anteriormente interpretadas como aberturas faríngeas son artefactos tafonómicos.
- Los análisis filogenéticos ubican a S. coronarius dentro de los Ecdysozoa.
Conclusiones:
- S. coronarius no es un deuterostomo temprano.
- Esta reclasificación expande la diversidad morfológica y ecológica conocida de los ecdizoos del Cámbrico temprano.
- El estudio revisa nuestra comprensión de la evolución animal temprana y el linaje deuterostomo.
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