Ancient sea sponges in 541-million-year-old fossils could be Earth’s first animals even before dinosaurs

MIT geochemists offer compelling evidence that ancient sea sponges were Earth's first animals, emerging over 541 million years ago. By analysing chemical fossils in rocks, researchers identified molecular traces unique to sponges, predating the Cambrian explosion. This discovery, validated globally and through lab experiments, reshapes our understanding of multicellular life's origins, establishing these humble filter-feeders as evolutionary pioneers.