Cambrian Fossils Reveal Single Nerve Cord Ancestry

In a groundbreaking 2025 study, international paleontologists unearthed Cambrian fossils (~520 Mya) indicating ancestral ecdysozoans, the ancestors of insects and worms, had a single ventral nerve cord. This overturns previous theories, showing that paired nerve cords evolved independently in modern groups like loriciferans and kinorhynchs to support more complex movements. Exceptionally preserved soft tissues made this discovery possible, highlighting the fossil record’s crucial role. Evolution just got a simpler twist!