Vertebrates include all the species of subphylum Vertebrata, that is, chordates with vertebrates. With currently about 66000 species, the vertebrates shows the prodigious majority of the phylum Chordata. Vertebrates comprise of jawed vertebrates, like bony fishes and cartilaginous fishes, and jawless fishes.
A vertebrate refers to a species with a backbone. The majority of the vertebrates exhibit bilateral symmetry. Coelomate animals exhibit a body cavity known as coelom with a complete lining known as peritoneum obtained from mesoderm. The majority of the bilateral animals, like all the vertebrates, are coelomates.
Vertebrates show incremental growth, like the incremental lines in the dentine of teeth. The majority of the animals more composite than jellyfish and other Cnidarians are divided into two classes, that is, the deuterostomes and protostomes. The chordates that include all the vertebrates are deuterostomes.
Thus, bilateral symmetry, coelom, incremental growth, and deuterostome development are the innovations found in vertebrates.
