The archaic sponge reef-dwellers of the Cambrian gave way to bryozoans—tiny, group-living animals that built coral-like structures. Ordovician reefs were also home to large sea lilies ...

You know that unsettling feeling you get when you're swimming in a freshwater body, and some underwater plant grazes your ...

The fossil content of local limestone shows the diversity of life in the late Ordovician period. Bryozoans and brachiopods, nearly equal in abundance, form about 60% of the allochems in local ...

Scanning electron micrograph of zooids of Watersipora grandis, a fossil cheilostome bryozoan. The specimen originates from the Pliocene Pinecrest Beds in Sarasota, Florida, North America. The ...

Previous reef-builders such as bryozoans were joined by corals and ... over the South Pole but the vast icecaps of the late Ordovician period melted almost to nothing. Sediments formed from ...