Both Norway and roof rats tend to dwell near human habitats. They live in large communities and are polygynous in nature. Rats live primarily on land and prefer to build their nests underground, in trees or in elevated areas within buildings.
Muskrats, on the other hand, are aquatic and prefer to live in the wetlands. Their populations are much less profuse. The muskrat is named for the musky odor is emits when threatened. Muskrats are extremely territorial creatures.
Muskrats have thicker tails than rats and can survive longer underwater. Muskrats look more like their relatives the beaver with their thick coat of fur and stocky appearance.