Mustela nivalis, commonly known as the weasel or the least weasel, is a small mammal of the genus Mustela. Other synonyms for this animal include the snow weasel, common weasel, and little weasel. These cute creatures have a slender, long body with short legs and a pointed snout. Their fur is a brownish or reddish-brown color with a white underbelly. They are found in many parts of the world, including Europe, Asia, and North America. Despite their small size, they are fierce predators, known to take down prey larger than themselves. Mustela nivalis play an essential role in the ecosystem and are an important part of the food chain.