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What is Rodent?

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The word Rodent has derived from the Latin word rodere which means ``to gnaw”. Rodent (order Rodentia). Rodents are mammals with more than 2,050 species and rodents can be found everywhere, they are extremely diverse. They can adapt to any environment and lifestyle, even a man-made environment. Rodents are the largest group of mammals. Not only that they constitute about half of the mammalian species. The majority of non-flying mammals are rodents. Rodent animals not only include mice but also rats, squirrels, porcupines, guinea pigs, hamsters, and beavers, etc. Three main categories of rodents are mice, squirrels, and cavy-like rodents. They use their sharp incisors to excavate burrows and defend themselves. Most of them are herbivorous; they feed on plant material and seeds they don't have any canine teeth their incisors grow throughout their life. Rodents lower classification includes Hamsters, Chinchilla, Capybara, Weaver Mongolian gerbil, Rat Agouti, Lowland Paca, Tuco-tuco, and red-crested tree-rat. Rodent family is a very diverse family of animals, it includes porcupines, marmots, pocket gophers, etc. Rodent species of animals are generally characterized by pairs of ever-growing rootless incisors. Most of the features of rodent animals are similar.

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General Characteristics of Rodents 

Rodents are typically small animals including rats, mice, guinea pigs, rats, hamsters, and many more. Their average lifespan is between four to eight years, though Black rats have the shortest lifespan of about 12months while Common degu has the longest lifespan among the Rodents which is about six to eight years. Pygmy jerboa is the tiniest rodent whereas Capybara is the largest living rodent. They arrived in Australia through Indonesia about 5 million years ago. Rodents are a group of mammals consisting of large front teeth which are also known as Incisors. They have a single pair of incisors which are chisel-shaped. As the word Rodent is Latin in origin which means to gnaw, they use their teeth for gnawing to get at food. Rodents are small animals that have sharp teeth and claws which they use for defense. Though they are small animals they prey on larger animals. They are very swift and have a sharp sense which helps them in danger.

Types of Rodents 

Rodent species are mostly found everywhere in all six continents except Antarctica. As they have survival instincts they are found both in wild and man-made environments.


 Rats are generally long-tailed rodents with prominent large eyes. In India brown rats are very common so it is also known as common rats. Brown rats(also known as Norway rats ) have small ears, a blunt nose, and have a thicker body compared to other black rats. They usually eat around 30gms of food. Rats are the rodents of the superfamily Muroids. Though the genus Ratta of the rats is considered as “true rats”. Packrats (genus -Neotoma), bandicoot rats (genus -Bandicota), and kangaroo rats(genus-Dipodomys) are examples of rats with other genera.


Especially in the western hemisphere Hamsters are most commonly kept as pets. The sub-family of Hamsters is Cricentinea. Hamsters contain 19 species classified into seven genera.  Golden hamsters or Syrian hamsters are considered the best species. The lifespan of Chinese Hamsters is about two to three years and their height is about 8.2 to 12 cm.  Syrians are the largest species found, their length is about 5 to 7 inches.


African pygmy has a lifespan of two years whereas Pachyuromys duprasi has five to seven years. Because they are mammals, and also because they share a high degree of homology with humans, mice are common experimental animals in laboratory research of biology and psychology fields primarily. When observed virtually all mouse genes have human homologs and the mouse genome has been sequenced quite a few times. Mice have always served as a staple in the diet of many small carnivores like cats and snakes alike. Humans have eaten mice since prehistoric times. During Victorian Britain times, fried mice were given to children and served as a folk remedy for bed-wetting. Throughout eastern Zambia and northern Malawi, mice are considered a delicacy where they serve as a seasonal source of protein.


Rodents, especially rats and mice, will play a major role in biomedical research. They are usually scavengers. Rodents can carry many diseases like hantavirus, leptospirosis, and lymphocytic. Hantavirus pulmonary syndrome causes severe illness. Washington every year reports about 1 to 5 Hantavirus cases. Plague is another serious disease which was led by Rodents like mice and rats. Bubonic plague was spread by rats to humans. The red-crested tree rat or Santa Marta toro is a type of tree rat. Is santamartamys and the family is Echimydae. It measures between (51 to 122 )cm. Rodents are serious pets of plantation crops and fodder Bandicota bengalensis cause serious trouble to farmers as they destroy a large number of crops and fields. ‘ Millardia melted in dryland areas. Though Rodents like hamsters and Guinea pigs are kept in homes as pets.

Did You Know 

Rodents reproduce crazily. What animals are Rodents? Rodents are small size animals with long chisel-shaped incisors. Rats and mice are prolific during reproduction. Mice generally have 5-6 babies. Whereas rats can produce litter 15 times every year Rodents usually don't leave long. Some Rodents can even swim, for example, mice and rats can tread in water for up to 3 days. They even can survive after being flushed in the toilet. The most interesting fact about Rodents is that they cannot throw up or burp. In between their esophagus and stomach, they have a powerful barrier that prevents them from vomiting. However, Rodents are interesting. No one wants this type of creature at home.

FAQ (Frequently Asked Questions)

1. What is Chinchilla?

Answer: Chinchillas are one of two species of crepuscular rodents. They are a bit larger and more robust than squirrels. They are found to be native to the Andes mountains which are located in South America. The Chinchilla has the densest fur of all the mammals that survive on the land. Also, the chinchillas are known after the Chincha people living in the Andes because they were the ones who once wore it owing to its dense and velvet-like fur. There are two living species of chinchilla namely Chinchilla chinchilla(formerly known as Chinchilla brevicaudata) and Chinchilla lanigera. Some of the feathers of C. chinchilla that are different from C.lanigera are that they have a shorter tail, a thicker neck and shoulders, and shorter ears. The former species is currently facing extinction; the latter, though rare, are often found within the wild. Domesticated chinchillas are considered to be of the C. lanigera species. 

Chinchillas show presbycusis. Mcfadden et al. found a little but significant decline of auditory sensitivity and outer epithelial cell function in 44 chinchillas examined between 3–15 years aged. This age-related deafness is analogous to age-related deafness in humans and more almost like humans than that of rodents with shorter life spans.

2. What is Beaver?

Answer: Genus - Castor. They are semi-aquatic 

Rodents. They are large in comparison to other Rodents. The length of Eurasian Beavers is about 11 to 30 kg, American Beavers is about 11 to 32kg. 

They are the second-largest Rodents. They are generally herbivores, they usually eat aquatic plants, grass, and tree barks. They have long chiselled-shaped incisors. They have brown or grey fur. Their feet are generally webbed as they are aquatic. They are also known as 

"Engineers of Ecosystem " The anal system if the Beavers usually releases oil.

They control the floods and erosion also. They are usually found all over North America except California. They are also present in the deserts of Nevada and parts of Utah. Beavers have generally orange-coloured teeth due it's protective coating. They not only live in ponds, lakes, or streams but also in the adjacent wetlands. Beavers usually slap their tails in the water which indicates danger. They are unique Rodents as they build scented molds. Beavers are extremely dangerous and f. Beavers attacks are fatal for domestic animals.

3. What is Gerbil?

Answer: Gerbillinae is one of the subfamilies of the rodent family Muridae which was also once known as desert rats. Almost all of the gerbils are primarily active during the day (also known as diurnal), and almost all of them are omnivorous. Gerbils have an average height of \150 - 300 mm which includes their tail as well as which makes up about half of their total length. One species, the good gerbil, Rhombomys Optimus, originally native to Turkmenistan, can grow to quite 400 mm. The average adult gerbil weighs about 70 g. One of the unique species of Gerbil, including the Mongolian gerbil Meriones unguiculatus which is also known as the clawed jird, is a gentle and hardy animal that has become a popular small house pet in many countries.

It is also used in some scientific research. During mating, copulatory plugs form within the reproductive tracts of females that hinder subsequent matings. The presence of those copulatory plugs suggests a polygynandrous mating system. Some gerbilline species breed year-round and a few breed seasonally. Females of most species are polyestrous and can bear multiple litters in a year. Some of the Gerbils also experience postpartum estrus and delayed implantation, such that the new litter begins its development as soon as first is weaned.

4. What is a Squirrel?

Answer: Squirrels belong to the family Sciuridae, a family of small or medium-size rodents. Amongst other rodents, the squirrel family also comprises tree squirrels, ground squirrels, chipmunks, marmots (including groundhogs), flying squirrels, and prairie dogs. Native to Eurasia, America, and Africa, humans introduced squirrels to Australia. Owing to its cuteness, squirrels are generally small animals, ranging in size from the African pygmy squirrel to the least pygmy squirrel at 10–14 cm in total length and just 12–26 gram in weight, to the Bhutan giant flying squirrel at up to 127 cm in total length. Typically having slender bodies, squirrels also have very long, very bushy tails and large eyes. Generally, a squirrel’s fur is silky and soft, though much thicker in some species than others. The coat colour of squirrels is highly variable. The word “squirrel” is derived from the Greek word skiers, meaning “shade tail,” which depicts one of the most obvious and distinguishable features of these small mammals.

5. What is Guinea Pig?

Answer: Belonging to the cavy family (Caviidae) Guinea pigs, (Cavia porcellus) is a domesticated species of South American rodents. Weighing about 500 to 1,500 grams, among rodents, domestic guinea pigs are fairly large, and have a body 20 to 40 cm long. The tail is not externally visible. Typically having a tassel of longer hairs at the neck, the texture and length of their fur vary from smooth (short or long) to coarse and short or long and silky. Guinea pigs tend to have extremely variable colouration: their coat ranges from white, cream, to chocolate brown, black, or a combined pattern. Hybridization and biochemistry studies suggest that Guinea Pigs are domestic animals that do not exist naturally in the wild. Originally domesticated as livestock for a source of meat, they are still consumed in some parts of the world. Beyond the simple fact that they are mammals, guinea pigs have many biological similarities to humans which make them useful in many fields of research. 

Guinea pigs have been used as experimental animals for centuries; hence the term guinea pig is also used colloquially to refer to a person who serves as a test subject in an experiment. The natural diet of a guinea pig is mostly grass; their teeth, especially their molars are efficient for grinding plant matter and have continuous growth throughout their life. Having significantly longer colons than most rodents, they must also supplement their diet by eating their feces a.k.a (coprophagy). Guinea pigs make great pets. Unlike most rodents, Guinea pigs have a longer life span and thus serve as pets for even longer. They have distinctive personalities and are quite active and vocal, making it easy to know their peculiar attributes and easily get attached. As you may see, from the various videos on the Internet they are very fun to play with and often entertaining.