1. A(n) is an example of an animal that is a chordate but not a vertebrate. 2. One of the features shared by all chordates is a(n) , a flexible rod that runs along the top side of the back. 3. All vertebrates have a(n) , an internal system of bones (in your case, 206 bones). 4. A(n) is an animal that has a backbone in addition to displaying the four features of all chordates. 5. A(n) is an animal that lacks a backbone and may or may not have all of the chordate features. 6. The phylum contains animals that share four specific anatomical features, including a hollow nerve cord and a tail.