On Gigantism in Early Carboniferous Brachiopods of the Order Chonetida

Giant brachiopods, including representatives of the order Chonetida, appeared in the second half of the Tournaisian and in the Viséan (Early Carboniferous). Based on known gigantism in extant organisms, the origin of this phenomenon can be associated with the maximum of a large Early Carboniferous transgression, which caused deepening of marine basins and a decrease in the temperature of the bottom water layers.