3 min read The Cambrian period, part of the Paleozoic era ... more readily than their soft-bodied precursors. These included brachiopods, which lived in shells resembling those of clams or ...

Internal, genetic factors were also crucial. Recent research suggests that the period prior to the Cambrian explosion saw the gradual evolution of a "genetic tool kit" of genes that govern ...

A volcanic eruption occurred during the Cambrian period. The pyroclastic flow and ... The pyroclastic flow even preserved ...