 Bryozoans have contributed to carbonate sedimentation in marine life since the Ordovician period. Bryozoans take responsibility for many of the colony forms, which have evolved in different taxonomic groups and vary in sediment producing ability. The nine basic bryozoan colony-forms include: encrusting, dome-shaped, palmate, foliose, fenestrate, robust branching, delicate branching, articulated and free-living. Most of these sediments come from two distinct groups of colonies: domal, delicate branching, robust branching and palmate; and fenestrate. Fenestrate colonies generate rough particles both as sediment and components of stomatoporiods coral reefs. The delicate colonies however, create both coarse sediment and form the cores of deep-water, subphotic biogenic mounds. Nearly all post- bryozoan sediments are made up of growth forms, with the addition to free-living colonies which include significant numbers of various colonies. “ In contrast to the Palaeozoic, post-Palaeozoic bryozoans generated sediment varying more widely with the size of their grains; they grow as they moved from mud, to sand, to gravel. ”
