Domain: Eukarya

True membrane bound organelles and nucleus.

Kingdom: Animalia


Lack cell walls


Phylum: Chordata

Notochord, a postanal tail, pharyngeal pouches, endostyle, and a dorsal nerve cord are displayed at some point during their life time along with motility

Class: Mammalia

Mammary glands, salivary glands, and hair

Giving parental care to newborns

Order: Carnivora

Feed primarily on freshly killed prey

Have canine teeth (rooted) and clawed digits

Family: Mustelidae

Small to medium sized Carnivores, long tubular shape, short limbs, and also fast hunters

Genus Species: Mustela nivalis

Feed mostly on rodents and insects

Smallest Carnivore

Do not hibernate

The common name for Mustela nivalis is the Least Weasel.

Mustela is defined as "one who carries off mice." After learning more about the Least Weasel, you will understand why Mustela fits them just right.

This Phylogenetic Tree was created based off morphological features. It includes all aspects of life and is a broad representation of life on Earth. The Least Weasel falls under the Animal category based on its features like motility, tail, and notochord. Molecular data differentiates the three domains, Bacteria, Archaea, and Eukarya.

Information included in the Phylogenetic Tree was found at

Below is a family tree featuring the Family Mustelidae. Note the physical similarities you may have noticed between the organisms found in the subfamilies of the family Mustelidae. This tree is based off morphological data and represents the organisms that are known for long slender bodies and short limbs. All of the organisms classified below are considered Carnivores, meaning they feed on other organisms.


Information was based off the Phylogenetic Tree found at

Weasels are most closely related to the Short-Tailed Weasel and the Long-Tailed Weasel. These weasels are even sometimes hard to tell apart.

The weasel shares some similarities with domestic dogs and cats both categorized as Carnivores.

Check out the Weasel's cousins below

Badger Sea Otter, and Martens

    Follow the weasel's tracks to his den!