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.
Hamsters and mice are two different species of rodent. of mammals. The smallest is the hog-nosed bat, which weighs 0.05 ounces. The largest is the blue whale, which can be 100 feet long and weigh 150 tons. But whether they live on land or water, all mammals share some common characteristics.