21
Nov
Hamsters belong to the Rodential orders of mammals. So, what exactly is a rodent?
Rodents are by far the largest mammalian order. Rodents are characterized by front teeth adapted for gnawing and cheek teeth adapted for chewing. Rodents have enlarged, chisel-shaped upper and lower front incisors that grow throughout their lives. These have hard enamel on the front surface and soft dentine on the back surface, so that unequal wear keeps the chisel edge sharp. There is a gap between the front teeth and the cheek teeth. When the lower jaw is in a forward position, for gnawing, the upper and lower incisors are in contact but the upper and lower cheek teeth are not; thus, wear on the cheek teeth is avoided. The cheeks are drawn in behind the incisors when the animal is gnawing, so that bits of hard material cannot be swallowed. When the lower jaw is pulled back into the chewing position, only the cheek teeth make contact.
The approximately 1800 rodent species are divided on the basis of their anatomy into 3 suborders. The Sciuromorpha, or squirrellike rodents, include the various species of squirrels, chipmunk, marmot, ground hog, prairie dog, gopher, pocket mouse, kangeroo rat and beaver. The Hystriomorpha, or porpupinelike rodents, include the porcupine, cavy, guinea pig, chinchilla, as well as many species whose name include the term rat (e.g., the South American bush rat).
Hamsters belong to the third suborder Momorpha, or mouselike rodents. Other animals in this category include the great variety of mouse and rat species, as well as lemming, vole, muskrat, gerbil, dormouse and jerboa.
The rabbits and hares were once classified as rodents because of their large, chisel-shaped incisors. However, they are quite distinct anatomically and have a long, separate evolutionary history; they are now classified in an order of their own, the Lagomorpha.
In 1839, British zoologist George Waterhouse reportedly found an elderly female hamster in Syria, naming it “Cricetus auratus,” the Golden Hamster.
Around 1930, zoologist and Professor at the University of Jerusalem Aharoni found a mother and litter of hamsters in the Syrian desert. By the time he got back to his lab, most had died or escaped. The remaining hamsters were given to the Hebrew University in Jerusalem, where they were successfully bred as Golden Hamsters. They were a bit bigger than the ones Waterhouse found, so they were named “Mesocricetus auratus”, although they were probably the same species.
The hamsters were shipped to labs all around the world. They arrived in the United Kingdom in 1931, and in 1938 reached the United States. Just about all Golden Hamsters are descended from the original litter found in Syria except for a few that were brought into the United States by travellers who found them in the desert. A separate stock of hamsters was imported into the US in 1971, but it isn’t known if any of today’s North American pets are descended from them.
The Dwarf Campbells Russian, Winter White Russian and Chinese were all introduced to the pet market in the United Kingdom in the 1970s, and the Roborovski hamster came from Holland into the UK in 1990.
Hamsters are now used for scientific research. Because hamsters are so disease-free and breed so rapidly (they can have a new litter every month!) and because they are so friendly and easy to handle, they are a popular choice among scientists. They are often used for cardio-vascular research, as their cardio-vascular system is remarkably similar to that of the human.
In the wild, hamsters are a nuisance to farmers. Hamsters have been known to hide in excess of 60 pounds of grain to feed them through the winter.
Next, we will be talking about the different breeds of domestic hamsters. I have a pair of hamster right now. They’re both cute and adorable and feisty. Heheheh…
We will also be talking about breeding them and how to take care of your pet hamsters. ^_^
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