I think the answer is vibrssae or whiskers.
To show the different levels of classification and divide among species, and different organisms on planet Earth. It also creates a universal "language" for scientists around the world when referring to organisms (cougar & puma are the same animals; different name)
Example: The American Alligator and the Chinese Alligator (look it up!) are in the same family and genus, but are not the same species.
Water. water does move but is not alive
