What does the term vertebrate mean?

The term vertebrate refers specifically to animals that possess a backbone or spinal column, which is a defining characteristic of this group. This backbone provides structural support and encases the spinal cord, which is crucial for the central nervous system. Vertebrates encompass a wide range of species, including mammals, birds, reptiles, amphibians, and fish.

In contrast, the other options do not accurately depict vertebrates. For instance, animals with wings may include birds and bats but do not encompass all vertebrates, as many do not have wings (like mammals and reptiles). Similarly, while the idea of walking upright pertains to bipedalism, not all vertebrates exhibit this trait; many vertebrates, such as quadrupedal animals, walk on four limbs. Lastly, while some vertebrates do have feathers, such as birds, not all vertebrates fall into this category, as fish and mammals do not have feathers. Thus, the correct choice highlights the essential anatomical feature that categorizes these animals.