El reanálisis de un fósil brasileño cuestiona los orígenes de los animales primitivos

12 de mayo de 2026

Reportado por IA

Un grupo de científicos ha determinado que unas estructuras, consideradas anteriormente como rastros de pequeños animales en rocas brasileñas de 540 millones de años de antigüedad, son en realidad comunidades fosilizadas de bacterias y algas. El nuevo examen utiliza técnicas de imagen avanzadas para revelar células preservadas y material orgánico.

Los investigadores se centraron en microfósiles de la formación Tamengo, en Mato Grosso do Sul. Estudios previos habían interpretado las marcas como pruebas de criaturas similares a gusanos que se desplazaban por el sedimento del lecho marino durante el periodo Ediacárico, justo antes de la explosión cámbrica de la vida compleja. Un nuevo análisis con microtomografía y espectroscopia Raman en el acelerador de partículas Sirius mostró estructuras celulares en lugar de rastros animales.

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12 de mayo de 2026 04:54