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 ...

The Museum holds the best collection of fossil bryozoans in the world, with more than 5,000 type and figured specimens. The collection contains an estimated 1,500,000 specimens, making it one of the ...

The Ordovician world was a watery one in which vast oceans covered almost the entire northern hemisphere. In the south, the mega-continent of Gondwana drifted. According to the University of ...

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 ...