People love otters. They hold hands when they sleep. They look soft and cuddly. They juggle rocks. Baby otters raised in captivity squeak when introduced to water for the first time.
However, there’s some confusion out there about whether otters are rodents, and which animal family the otters fall into.
In this post, we’ll address some widespread misconceptions and break down the differences between the two.
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Are Otters Rodents?
No, otters are not rodents; they do not belong to the rodent family.
Otters are carnivorous mammals that belong to the family Mustelidae, also known as the weasel family. This family includes weasels, badgers, otters, ferrets, martens, minks, and wolverines, among others.
Otters are one of over 280 species of the order Carnivora, the fifth-largest order of mammals.
Rodents, on the other hand, belong to a completely different order called Rodentia. Not only otters are not classified as rodents, but also belong to a different clade.
Let’s explain this more simply and in detail.
Otters Are Taxonomically Different From Rodents
In biology, there are millions of different plants, animals, bacteria, fungi, etc. To look at them more easily, scientists organized all of these organisms into different groups called taxa.
Remember how a grocery store is organized?
One huge building is divided into departments such as fruit, dairy, meats, cosmetics, etc.
Then, each department is further divided into aisles, every aisle into categories and brands, and then finally we get to the individual products. This organization from larger to smaller, more specific categories, is called a taxonomic hierarchical system in biology.
At the top, the largest category is called domain. This is our grocery store building.
Within each domain, there is a second category called a kingdom. This is our store department.
After kingdoms, the subsequent smaller categories are phylum, class, order, family, genus, and species.
The more categories two animals share in common, the closer they are related.
Otters and rodents belong to the same kingdom, Animalia, or animals. They are both members of the same phylum, Chordata, and of the same class, Mammalia, or mammals.
This is where the relationship between these animals stops; rodents are members of the order Rodentia, while otters are members of the order Carnivora.
Otters belong to the Mustelidae family, while rodents can belong to one of 30 different rodent families.
This means that otters are also not members of the rodent family.
Mustelids are some of the oldest carnivorous animals that ever existed. They first appeared in evolutionary history some 40 million years ago. Most mustelids have long bodies, short legs, and thick fur – the largest of all mustelids is the sea otter which can reach almost 100 pounds.
What Are Rodents?
Rodents are small, gnawing animals that have no canine teeth and whose incisors continuously grow. Specifically, they have two pairs of sharp incisor teeth, one pair in the lower and another in the upper jaw.
The rodent family is the largest order of animals today – it is estimated that almost half of all mammal species are rodents. They are native to all major landmasses except for New Zealand, Antarctica, and several oceanic islands, but they have been slowly introduced there.
Examples of rodents include mice, rats, squirrels, prairie dogs, porcupines, beavers, guinea pigs, and hamsters.
Why Are Otters Not Rodents?
Otters are not rodents because they belong to a different mammal order.
Otters are carnivorous mammals that feed on fish and invertebrates, and because of their unique characteristics, they belong to the Carnivora order together with cats, dogs, hyenas, bears, raccoons, and many others.
Otters have four sharp canine teeth they use to crush invertebrate shells or to cut, bite, and tear animal meat.
Unlike otters, most rodents are herbivores and feed on plants. They also have a single pair of continuously growing incisor teeth in each of the upper and lower jaws.
What Are Otters?
Otters are very intelligent and social animals found in rivers and seas around North America, Asia, Europe, Africa, and the Pacific.
There are 12 species of otters today, including spotted-necked otters, marine otters, African clawless otters, and many others. The 13th otter species, the Japanese river otter, was declared extinct in 2012.
The two otter species found in North America are river otters and sea otters.
Otters have been hunted for their pelts from at least the 17th century; around the 18th century, thousands of them died during the California fur rush. Otter fur is unique because they have the densest fur among animals. It is said that there are between 800,000 and 1 million individual hairs per square inch of otter fur.
They are very adapted to hunting in water. Because of their webbed feet and strong bodies, otters can reach a top swimming speed of around 9 mph. This is a lot faster than the record 6 mph Michael Phelps achieved in 2010 in freestyle swimming.
Otters also have such a strong sense of smell that they can smell their prey underwater.
They are also very useful animals that help fight climate change. Sea otters, for example, feed on sea urchins. Sea urchins eat massive amounts of seaweed; seaweed helps fight climate change by absorbing carbon emissions.
More otters mean fewer sea urchins, more seaweed, and less global warming.
But, otters are not as brilliant as it seems. They are known to attack humans, hold each other’s pups hostage for food, kill animals for fun, and do lots of other disturbing things.
Read More: Is A Lemur A Marsupial?
In conclusion, otters are neither rodents nor marsupials. Otters are mammals that belong to the order of placental mammals called Carnivora. They also give birth to live young.
Carnivores can be divided into two groups: the cat-like Feliformia, and the dog-like Caniformia. The main difference between the two is the structure of their ear bones and some skull features.
The feliforms include cats, hyenas, mongooses, and civets. The caniforms include dogs, bears, raccoons, weasels, and seals. Otters are members of the caniforms.
The main difference between otters and rodents is that otters are carnivorous and do not have as pronounced incisor teeth as rodents do. Most rodents are herbivores.
Rodents are the largest order of small mammals, and one of the most common of all animal types.
If you were pondering on the question “are otters rodents”, we hope this article removed all doubts.