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Comentario sobre "La ultrastructura revela el esqueleto faríngeo ancestral de los vertebrados en los yunnanozoos"
Kaiyue He1, Jianni Liu1, Jian Han1
1Shaanxi Key Laboratory of Early Life and Environments, State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University (NWU), Xi'an 710069, P. R. China.
Science (New York, N.Y.)
|July 27, 2023
Resumen
Yunnanozoans no son vertebrados del grupo del tallo. Los análisis de ultraestructura y morfología de más de 8000 especímenes refutan la presencia de características clave de los vertebrados, lo que desafía las propuestas filogenéticas anteriores.
Área de la Ciencia:
- Paleontología
- Biología del desarrollo
- Biología evolutiva
Sus antecedentes:
- Investigaciones anteriores propusieron a los yunnanozoos como vertebrados de grupo troncal basados en características anatómicas específicas.
- Estas características incluyen presunto cartílago celular, microfibras de fibrilina y una barra subcordal en los arcos branquiales.
Objetivo del estudio:
- Para reevaluar la posición filogenética de los yunnanozoos.
- Investigar la ultrastructura y la morfología de los yunnanozoos para confirmar o refutar las afinidades de los vertebrados.
Principales métodos:
- Análisis ultrastructural detallado de las muestras de yunnanozoos.
- Examen morfológico completo de más de 8000 ejemplares de yunnanozoos.
- Análisis comparativo con taxones conocidos de vertebrados e invertebrados.
Principales resultados:
- Se confirmó la ausencia de cartílago celular en los yunnanozoos.
- Se ha demostrado la ausencia de microfibras de fibrilina.
- La estructura de la barra subcordal no fue identificada como homóloga a las estructuras de los vertebrados.
- La evidencia morfológica y ultrastructural no apoya las afinidades de los vertebrados.
Conclusiones:
- Yunnanozoans no son vertebrados del grupo del tallo.
- La colocación filogenética propuesta anteriormente se rechaza sobre la base de nuevas pruebas.
- Se necesita más investigación para determinar la posición filogenética precisa de los yunnanozoos dentro de los metazoos.
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