Even though rats and mice have poor eye-sight, they have an excellent sense of smell and hearing as well as an Olympic level of athleticism with not only their feet but also with their teeth. They can climb wires and pipes vertically and completely gnaw through concrete, wood, and metal structures. These rodent's teeth are constantly growing, so they must chew on hard surfaces in order to keep the size of their teeth at a comfortable level. Rats can have territories of up to twenty miles and can even jump up to six feet high! Scientists think the very first mammal in the evolution of animals was a tiny, Jurassic shrew the size of a house mouse, and this eventually led to the evolution of the mouse, rat, and the human.