Which animal are all tetrapods derived from?

fuse with backbone all thrust when animal moves forward. vertebrate. zygapophyses (support and flexibility protection). ribs. can also protect lungs. skull & neck. -skull shortened and snout elongated -head separated by neck, allows head to be lifted -2nd vertebrate added to allow for side to side movement. fishapod-tiktaalik. read more

An animal that possesses a true coelom (fluid-filled body cavity lined by tissue completely derived from mesoderm). Protostomes Protostomes are characterized by spiral cleavage, schizocoelous development, and the mouth generally developing from the blastopore, and it is for this characteristic that the term protostome derives (from the Greek protos, first, and stoma, mouth). read more

Tetrapods evolved from a finned organism that lived in the water. However, this ancestor was not like most of the fish we are familiar with today. Most animals we call fishes today are ray-finned fishes, the group nearest the root of this evogram. Ray-finned fishes comprise some 25,000 living species, far more than all the other vertebrates combined. read more