Brown Rat

Also called the common rat, the brown rat is the ancestor of today's pet rats. The brown rat is a highly adaptable animal. Infact, it is the most successful mammal on the planet after humans. This rat is perfectly comfortable living around humans, often even in our homes. Most scientists think that the rat first originated in China, and gradually spread to cover most of the world. The brown rat is a good swimmer, both at the surface and under, and is surprisingly intelligent. Their teeth, like the teeth of many rodents, are always growing. The enamel on the front of the teeth is very hard and strong, while the enamel on the backside is relatively weak. This means, that when the rat chews, it will wear down the backside of the tooth, and not the front. In doing this, the rat is self-sharpening it's own teeth! Now that's a smart little rodent.