Polychaetes, segmented worms bearing parapodia, are first found in the Cambrian Period, and all exhibit an elongated body broken into many segments. More specifically, the Polychaete worms within the order Eunicida are also first found in the Cambrian and are further characterized by ventral maxillae and dorsal mandibles positioned within the pharynx. Eunicids are foundContinue reading “Polychaetes”