Gadzira shanduro yakaoma zvikuru yemutsara uyu Ordovician inoratidzira nhambo yokupedzisira huru yokusiyanisa pakati pama trilobites: mienzaniso mishomanene zvikuru mitsva chose chose yesangano yakabuda pashure peOrdovician.
Zvechokwadi, shanduro yakaoma zvikuru yemutsara uyu ndeiyi "The Ordovician marks the last great diversification period among the trilobites, very few entirely new patterns of organization arose post-Ordovician; later evolution in trilobites was largely a matter of variations upon the Ordovician themes".