1 Multiple sclerosis (MS) is a disease that causes demyelination (disruption of the myelin that insulates and protects nerve cells) of spinal nerve and brain cells.  Although the exact case is unknown, multiple sclerosis is considered to be an autoimmune disease.
The skunk is not a rodent. They belong to the family Mephitidae and the order Carnivora which does not include rodentia. They are sometimes placed in the family Mustelidae (weasels) but have been discovered to be less related than was thought.
The single largest group of mammals is the Rodentia. Most non-flying mammals are rodents: there are about 1,500 living rodent species (out of about 4,000 living mammals overall). Most people are familiar with mice, rats, hamsters, and guinea pigs, which are commonly kept as pets.he Rodentia also includes beavers, muskrats, porcupines, woodchucks, chipmunks, squirrels, prairie dogs, marmots, chinchillas, voles, lemmings, and many others. (Incidentally, the Rodentia does not include rabbits; rabbits differ from rodents in having an extra pair of incisors and in other skeletal features.