When someone says rodent, what’s the first thing that comes to mind? If you imagined a rat or a mouse, you aren’t alone! But what about rabbits, are they rodents too?
So, are rabbits rodents? No, rabbits are not rodents. Rabbits and hares belong to the family Leporidae, in the order Lagomorpha. Rodents, on the other hand, belong to the order Rodentia which is the largest group of mammals. While rabbits were originally classified as rodents, there are a few differences between them.
If you are interested in learning why rabbits aren’t rodents, keep on reading! In this article, we will tell you what are the main differences between rabbits and rodents.
Difference Between Rabbits and Rodents
Despite popular beliefs, and what you may have learned in school, rabbits aren’t rodents!
Over 100 years ago, in the early 20th century, scientists at the Smithsonian Institute started to study the differences between rodents and rabbits. They discovered that Lagomorphs, like rabbits, have diverged separately from their rodent cousins and also have a number of different traits.
The main differences between rabbits and rodents are:
Although their teeth appear similar, many differences set them apart.
First off, rabbits have an extra pair of incisors whereas rodents have only one set. The second pair of rabbit incisors is smaller and tucked behind a much larger pair of main teeth in the upper jaw. This means that rabbits have naturally more teeth than rodents.
Unlike rabbit incisors that are covered in hard enamel on both sides, rodent teeth only have a layer of enamel on the front. In rodents, the back of the tooth is covered by a layer of dentine, making the front of a rodent’s teeth much harder than the back.
When it comes to teeth rabbits and rodents have one thing in common, their incisors grow continually. This is called indeterminate growth and happens because the base of the incisor is rootless and open allowing the tooth to keep growing.
Since their incisors continue to grow all the time, rabbits and rodents have to chew to wear down their teeth and prevent them from overgrowing (source).
In rodents, gnawing results in the wear of the soft dentine in the back of the tooth causing a sharp and chiseled shape. On the other hand, rabbit teeth can never develop that level of sharpness since they are completely encased in enamel.
Another thing that sets rabbits and rodents apart is the color of their teeth. The outer layer of a rodent’s teeth ranges in color from orange to orange-yellow whereas a rabbit’s teeth should always be creamy white.
Both rodents and rabbits can eat plant matter. But, while rabbits are obligated herbivores, rodents are omnivores and can eat insects, plants, roots, grains, and nuts.
As obligate herbivores, rabbits break down food like other hooved animals and have a different digestive tract than rodents. Like cows and horses, rabbits have a cecum that is a pouch filled with good bacteria that helps break down and ferment cellulose from plants (source).
Now, for the nasty stuff. When rabbits eat plant matter they maximize digestion by eating their own poop! Let’s dig into the gory details, shall we?
Whatever plant matter the rabbit eats, it passes down their digestive system in the form of a soft pellet known as caecotroph. This is then eaten, re-chewed, digested, and pooped out in a form we are all familiar with – a hard round pellet.
It’s worth noting that a few rodents, mainly chinchillas and guinea pigs have cecum as well and eat their own poop. However, these are the only known exceptions in rodents.
Male rabbits and male rodents have two scrotal sacs that can be contracted in their body cavity when necessary. Both species have a short gestation period, but that’s where all similarities end!
Rodents, like most mammals, have a baculum, or a penis bone, that helps harden a male’s penis allowing them to mate for longer periods of time. Rabbits, on the other hand, don’t have baculum bones.
Having a penis bone, allows rodents to mate longer and faster providing an immediate erection. This evolutionary adaptation is handy because it decreases the amount of time the animal spends in a compromised position being exposed to predators.
What Family Does a Rabbit Belong to?
Rabbits are small mammals in the family Leporidae, one of the two families in the order Lagomorpha. The other family is pika, scientifically known as Ochotonidae.
Generally kept as pets, rabbits have long ears, long hind legs, and short fluffy tails. While there are several different species of rabbit within the Leporidae family, the European rabbit, Oryctolagus Cuniculus is the most commonly kept as a family pet.
How Closely Related Are Rabbits and Rodents?
Although they are now members of different orders and families, rabbits and rodents are closely related. In fact, in the early 20th century, rabbits were classified as rodents, together with rats, mice, hamsters, guinea pigs, and many others.
Although they are close relatives, rabbits and rodents differ in many ways. While they are similar in terms that their teeth grow continuously, rabbits do have an extra set of incisors.
While they were once classified as members of one family, rabbits aren’t rodents. Rabbits and hares are Lagomorphs, but rodents belong to the order Rodentia that consists of rats, mice, guinea pigs, chinchillas, and many others.
While they are similar in many ways, there are several key differences between rabbits and rodents!
Unlike rabbits, rodents can spend more time mating thanks to a penis bone, known as a baculum. On the other hand, rabbits have an extra set of incisors and a cecum pouch that allows them to maximize the number of nutrients they absorb by eating poop.