Probably more than you'll ever need to know about hamsters....

There is a common hamster (Cricetus cricetus) that can be found on the steppes or cultivated land in Europe into western Asia. These are the largest of the hamster species and can be 20-30 cm (8-12 inches) long. They tend to be brown with dark or black fur on their bellies. But these are not the hamsters that "we all know"; the ones that are pets. So we look toward the most commonly kept one, the Syrian or golden hamster (Mesocricetus auratus).

Golden Hamster

While they were undoubtedly known to farmers and some others, the history of the hamster largely begins in the 19th century (though the first description occurs in 1797). In 1839, George Robert Waterhouse, Curator of the London Zoological Society, named and presented the golden hamster for the first time (originally Cricetus auratus, the name change was because they were smaller than the common hamster but larger than what is commonly called the dwarf varieties). It was an elderly female that he had found in Syria. The fur was displayed in the British Museum for a time and is still housed at the Natural History Museum in London.

His description:

[It] is remarkable for its deep golden yellow colouring. The fur is moderately long and very soft and has a silk-like gloss; the deep yellow colouring extends over the upper parts and the sides of the head and body and also over the outer parts of the limbs; on the back the hairs are brownish at the tips, hence this part of the fur assumes a deeper hue than on the sides of the body; the sides of the throat and upper parts of the body are white, but faintly tinted with yellow; on the back and sides of the body, all hairs are of a deep grey or lead colour at the base. The feet and tail are white. The ears are of moderate size, furnished externally with whitish hairs. The moustaches consist of black and white hairs intermixed....
There may have been a group that was brought to England in 1890s and bred for a time but they did not continue and the line died out for whatever reason (only one source mentions this). The next step in the history comes in the late 1920s. A parasitologist at the Hebrew University in Jerusalem was working with Chinese hamsters (see below). Finding them difficult to breed and cost prohibitive to have shipped from China, he wanted a more localized species.

A colleague went to Syria and after some digging (literally) managed to find a female and litter. The female was killed due to the zoologist placing her with the young, not realizing that hamsters are primarily lone creatures and tend to be aggressive toward each other, up to and including killing and/or eating their young (though often as a means of controlling the number so that the surviving ones can be better cared for). Dwarf hamsters are an exception; they mate for life and the male helps care for the young.

They were brought back and after some escapes (don't try putting hamsters in wooden cages), they were successfully bred. There were at least 150 by the end of the year. And hamsters are reproductively successful. The golden hamster reaches puberty at 4-5 weeks, estrus is every 3-4 days, and the gestation period is 16-18 days (meaning as much as a litter a month is possible). A litter can consist of 1-18, with 8 being the average.

Because they were so easily bred, fairly tame, disease-free, and clean, they became popular for medical and other animal experimentation. Their cardiovascular system is remarkably similar to a human's. Members from the colony of that original litter were eventually shipped all over. In 1931, the first ones were brought (smuggled in the scientist's pockets) to England. In 1938, the hamster arrived in America. Almost every golden hamster is descended from that original litter from Syria.

Since the late 40s/early 50s, the golden hamster has become a popular pet and been bred into a number of colors (cinnamon, rust, dark grey, light grey, yellow, cream, black) and varieties of fur (short hair, long hair also called "Teddy Bear," satin, even a "hairless" variety). They tend to be about 15-20 cm (6-7 inches) long.

Other Hamsters Kept as Pets

Two species from Russia have also become popular as pets. The Dwarf Winter White Russian was first described in 1770 and first bred in labs in Germany in the 1960s. It was introduced to British labs in the 70s and became a "pet" around 1978. As with the golden hamsters, most are descended from the original litters kept in bred in the lab. The Dwarf Campbells Russian hamster was discovered in 1905 and first brought to the United Kingdom in 1963. They were breeding in captivity by 1968 and in the early 70s a pair was obtained by a hamster club, followed by more later. They didn't become popular or common as pets until the 1980s. Both species grow to about 8-10 cm in length and are native to the central and Eastern areas of the former Soviet Union. Due to the climate, they both have fur on the bottom of their feet and the Winter White's fur can change white in the winter (triggered by the shortening of daylight hours).

First recorded in 1900, the Chinese hamster is not as commonly kept as a pet. It is a native of Northern China and Mongolia. Another "lab hamster," it was introduced as a pet in the 1960s. They are difficult to breed and have a "mouse-like" appearance. It is small like the Russian Dwarves, growing to a length of 8-10 cm.

There is another one kept as a pet, the Roborovski hamster. Another native to the northern China, Mongolia area, this is the smallest hamster kept as a pet at only 4-5 cm in size. They were discovered in 1894 but not bred in captivity until the 1970s. They are generally not found in pet stores, requiring specialty breeders for purchase.

Other Hamsters

There are over a dozen other species and subspecies of hamsters that are, like the common European one, not kept as pets or bred in captivity. There is even a rodent (not actually a hamster) called the South American Hamster (a.k.a. the "White Tailed Mouse" or "Maned Rat"). It was once referred to as the Maned Hamster or Crested Hamster.

Hamsters, in General

All Hamsters belong to the family Cricetidae and the order Rodentia ("rodent," coming from the Latin rodere, meaning "to gnaw"). In the wild, they tend to live in dry or somewhat arid, even desert, areas. They live in burrows beneath the ground where they store grain (carried in their characteristic expandable cheek pouches), their primary food source. That first litter of golden hamsters was discovered eight feet below the surface and farmers in the Middle East have been known to find as much as 30-60 pounds of grain stored below the ground. They also are known to eat some fruits and vegetables and some even insects or small animals (I would assume only the larger species, cannibalism aside).

They have rather poor eyesight, but a good sense of smell and hearing, helping them, being nocturnal animals (as anyone knows who's been kept up at night, listening to one chew on the bars of the cage or run in that damn wheel). They have only a small nub of a tail (the large common hamster has one only 3-6 cm). Despite their somewhat rounded and fuzzy appearance, they are able to squeeze into relatively small spaces. Generally, they live about two years, but some have been known to live up to four.