vertebrates
The first eight phyla listed in Table above include only invertebrate animals. Invertebrates are animals that lack a vertebral column , or backbone . The last phylum in the table, the Chordata, also includes many invertebrate species. Tunicates and lancelets are both invertebrates. Altogether, invertebrates make up at least 95 percent of all animal species. The remaining animals are vertebrates. Vertebrates are animals that have a backbone. All vertebrates belong to the phylum Chordata . They include fish, amphibians, reptiles, birds, and mammals.