Reanálise de fósseis no Brasil desafia teorias sobre a origem dos primeiros animais

12 de maio de 2026

Reportado por IA

Cientistas determinaram que estruturas antes vistas como vestígios de pequenos animais em rochas brasileiras de 540 milhões de anos são, na verdade, comunidades fossilizadas de bactérias e algas. O reexame utiliza imagens avançadas para revelar células preservadas e material orgânico.

Os pesquisadores concentraram-se em microfósseis da formação Tamengo, no Mato Grosso do Sul. Trabalhos anteriores haviam interpretado as marcas como evidências de criaturas semelhantes a vermes movendo-se pelo sedimento do fundo do mar durante o período Ediacarano, pouco antes da explosão cambriana de vida complexa. Uma nova análise com microtomografia e espectroscopia Raman no acelerador de partículas Sirius revelou estruturas celulares em vez de rastros de animais.

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terça-feira, 12 de maio de 2026, 04:54h