nemo fish

active ambient amphibians anglerfish aquatic armor arthropods biology bodied bodies body bony cartilaginous classification deepest defined developed diversifying diversity earliest ectothermic era evolve external finned fish fishes formal formidable grouping gulpers hagfish higher jaws large lobe marine negatively oceans organisms paleozoic pisces predators prey protected rather shark soft streams swimmers systematic taxonomic temperature them tuna typological variety vertebrates water wide