i dont know but u can ask siri on an i phone and the next answer is cows
A scientist classifies an animal as a vertebrate if it has a spinal cord, or notochord. Most vertebrates have a backbone, but the Phylum Cephalochordata do not have backbones but are still classified...
We wouldn't know as much as we do now! Scientists are good peeps...!
for systematic study of that thing
to sort things Also to help themselves learn about them, and evolution. maybe to let themselves grasp the diversity of it all.