Subphylum: Vertebrata
Vertebrates have not only a hollow tube along their back through which a nerve cord from the brain runs, but also supporting and protective structures around that nerve cord (typically vertebrae) and around the brain (a skull).
Vertebrates can be either ectothermic (cold-blooded), having a body temperature that is the same as the temperature of their environment, or endothermic (warm-blooded), having a body temperature that is independent of the temperature of their environment.
Is your animal endothermic, or ectothermic?
