The Earliest fish appeared in the course of the Cambrian as smaller filter feeders; they continued to evolve with the Paleozoic, diversifying into numerous varieties. The earliest fish with devoted respiratory gills and paired fins, the ostracoderms, experienced significant bony plates that served as protecting exoskeletons towards invertebrate predators. Fishes https://maps.app.goo.gl/kTisAZCbSjAw6nkX8