Confirmation that bryozoan animals were present during the Cambrian explosion
Summary
Newly discovered Cambrian fossils indicate that bryozoans, colonial marine invertebrates, were already present and diversified during the Cambrian explosion. This overturns the long-held view that the phylum was absent from early Cambrian ecosystems.
Why it matters
It rewrites a key branch of the animal tree and tightens the timeline for how complex marine ecosystems formed early in Earth’s history.