A hamster's diet should consist of mostly high-quality, store-bought food that is designed especially for your furry pet. You can feed hamsters several different human foods as long as they are healthy. Hamsters can eat the following fruits: MORE?
Roborovski hamsters (Phodopus roborovskii; formerly, Cricetulus bedfordiae) or desert hamsters (also known simply as Robos or Robs) are the smallest of all dwarf hamsters, averaging under 2 cm (1 inch) at birth, and between 4.5-5 cm (2 inches) and 20-25 g (1 oz) during adulthood. Distinguishing characteristics of the Roborovskis are eyebrow-like white spots and the lack of any dorsal stripe (found on the other members of the Phodopus genus). The average lifespan for the Roborovski hamster is three years, though this is dependent on living conditions (extremes being four years in captivity and two in the wild).][ Roborovskis are known for their speed and have been said to run an equivalent of four human marathons each night on average, a fact that famed hamster scientist Tanner Lewis confirmed in 2012. It is one of three species in the genus Phodopus.
Roborovski hamsters live in and around Russia's deserts and the adjacent territories of Kazakhstan, and northern China. Their efficient use of water makes them particularly suited to the steppe and desert regions they inhabit. They dig and live in burrows with steep tunnels as deep as six feet underground. In the wild, Roborovski hamsters are crepuscular, being most active at dawn and dusk.
They are omnivorous; they primarily eat grains, vegetables, fruit, and plants, but they will also eat meat and insects in small quantities. Roborovski hamsters remain underground in winter and survive in that season by stockpiling some food in warmer weather and storing it in special food chambers within their burrow system.
Lt. Vsevolod Roborovski [Russian expeditioner] first made note of these hamsters, discovering them on an expedition in July 1894, though they were not studied scientifically for the best part of another decade, until Konstantin A. Satunin made observations in 1903. The London Zoo imported them into the UK in the 1960s, but the first Roborovski hamsters studied in Britain were imported in the 1970s from Moscow Zoo. (None of them, however, bore offspring.) Continental European countries had more success in breeding some Roborovskis, however, and those currently in the UK are descendants of a batch imported from the Netherlands in 1990. They were imported to the USA in 1998, though they are now commonly found in pet shops in several countries. In South Korea, they are almost as common as the winter-white Russian dwarf hamster.
Currently, 10 variations of Roborovski hamsters are confirmed.
Breeding in captivity has also produced a darker dilution of the naturally sandy-coloured agouti fur.
The gender of a Roborovski is determined visually; female openings are very close together and may even look like a single opening, while male openings are further apart. Males usually have a visible scent gland near the navel above the two openings, appearing as a yellow stain.
Roborovski hamsters may reach sexual maturity as early as five weeks, but usually do not breed until five months after they are born, usually in early spring. When keeping them as pets, females should not be mated until they are closer to four months of age. Males usually reach sexual maturity at three months. The gestation period of Roborovski hamsters is usually 22 days, but can be up to 30.][ As parturition grows closer, the female will become more aggressive towards the male and often banish him from the nest till after the birth. The female Roborovski hamster can bite an owner if she is handled while she is heavily pregnant. Litters are usually small, being typically four to six pups, though larger litters of up to 10 have been reported. If the male is still around the female shortly after she gives birth, he will often attempt to mate with her again.
Roborovski hamsters, being fast, agile, and naturally timid or shy, are generally recommended as "look but don't touch" pets. Loud noises can agitate them, and they are extremely skittish. As they rarely bite, Roborovski hamsters may make good pets for owners who enjoy interactive play (in which the hamster explores its owner). This may also provide time for taming them. As light may sometimes disturb them, red lights are recommended to allow an owner to view the hamsters without disturbing them; Roborovski hamsters are unable to see red light.
Roborovski hamsters are great climbers, like other hamsters. They also like to tunnel and run. Roborovski hamsters are known to sleep in their wheels, especially in wheels with banked edges.
Although claimed to be hypoallergenic, Roborovski hamsters have been associated with the development of asthma in previously asymptomatic owners.
Roborovski hamsters do not particularly take to eating the pellets found in most common retail hamster foods.
The Djungarian hamster (Phodopus sungorus), also known as the Siberian hamster or Russian winter white dwarf hamster, is one of three species of hamster in the genus Phodopus. It is ball-shaped and typically half the size of the Syrian hamster, and therefore called a dwarf hamster along with all Phodopus species. Features of the Djungarian hamster include a typically thick, dark grey dorsal stripe and furry feet. As winter approaches and the days shorten, the Djungarian hamster's dark fur is almost entirely replaced with white fur. In captivity, this does not always happen. In the wild, they originate from Dzungaria, the wheat fields of Kazakhstan, the meadows of Mongolia, Siberia, and the birch stands of Manchuria.
Djungarian hamsters are common as pets in Europe and North America, and exhibit greater variance in their coats than those found in the wild. They reproduce often—more so than Syrian hamsters—and, as they have no fixed breeding season, can continue to produce large amounts of offspring all year round. Young pups will act aggressively to one another; whilst breeding females may show similar aggression to males.
The coat of the Djungarian hamster is less woolly than that of the Campbell's dwarf hamster, and apart from the normal colouring, they can be coloured sapphire, sapphire pearl, or normal pearl. The head length of the Djungarian hamster is 70 to 90 millimetres in length, the length of the tail is five to 15 millimetres, and the hind legs are 11 to 15 millimetres. The body weight changes dramatically throughout the year. It is at its lowest from July to August. In males, the body weight ranges from 19 grams (0.67 oz) to 45 grams (1.6 oz), and in females, 19 grams (0.67 oz) to 36 grams (1.3 oz). In human care, they are slightly heavier. The average lifespan of the Djungarian hamster is one to three years of age in captivity, though they can live longer. In the wild, they are known to live as little as one year.
In summer, the fur of the Djungarian hamster on the back changes from ash-grey to dark brown, or sometimes pale brown with a tint. The face changes to grey or brown, while the mouth area, the whisker area and the ears are slightly brighter. The outer ears and the eyes have black edges. The rest of the head is dark brown or black. From the head to the tail runs a black-brown dorsal stripe. The throat, belly, tail and limbs are white. The ears are grey with a pinkish tint with scattered black hairs. The hairs on the underside are completely white. The bright coat the bottom extends to the shoulders, flanks and hips in three arches upward. It is distinguished from the darker fur on the top of the existing black-brown hair, three curved line.
Apart from the typical colouration, Djungarian hamsters can also be coloured pearl, sapphire, sapphire pearl and marbled. Other colorations are available, but these are strongly suspected to appear only in hybrid crossings with Campbell Dwarf hamsters. Some of these colorations are mandarin, blue, argente, yellow blue fawn, camel, brown, cream, merle and umbrous.
In the winter, the fur is more dense. They sometimes have a grey tint on their head. More than ten percent of the hamsters kept in the first winter develop the summer coat. In the second winter, only a few change into the winter coat and winter colour is less pronounced. The moulting in the winter fur starts in October or November and is completed in December, while the summer coat begins in January or February and is completed in March or early April. The ears are grey with a pinkish tint. Moulting both run jobs on the head and the back of the spine to the sides, the legs and the underside. The hairs grow longer in the summer, to about ten millimetres long.
The pigmentation of hair is controlled by the hormone prolactin and colour genetics. Day length must be less than fourteen hours to initiate the change to winter coat. The change to the winter coat can be triggered in the summer by the short day lengths. The change occurs back to the summer coat in the autumn, when the length of the days change again. At internal temperatures hamsters in captivity start later with the changes. The winter colour is less pronounced in them. The eyes of the Djungarian hamster are black, unless it is albino in which case they are red.
In the wild, the Djungarian hamster's fur changes colour in the winter. This adaptation helps them to evade predators in the snow-covered steppes of winter. The Djungarian hamster digs tunnels one metre deep leading to ground burrows where they can sleep, raise their young and hide from predators. The weasel is one of the Djungarian hamsters main predators. Most of these burrows have six entrances. In the summer time, the burrows are lined with moss. To keep the burrow warm in the winter, the Djungarian hamster closes all but one entrance and lines the burrows with animal fur or wool that it finds. The temperature inside the burrow is usually . Djungarian hamsters sometimes live in the semi-deserts in Central Asia. They also live in the dry steppes and wheat or alfalfa fields as well as on small fields in the forests of the region around Minusinsk. The fur on the Djungarian hamster's feet protect the feet from the cold ground from in the cold climates in the wild. The population density is highly varied. In 1968, the first four examples of the Djungarian hamster were caught in Western Siberia and brought to the Max Planck Institute in Germany.
The Djungarian hamster is a species of Phodopus. The Campbell's Dwarf Hamster is named as a separate species within the Phodopus sungorus species with respect to subspecies. Other subspecies are not distinguished. The Djungarian hamster was described by Peter Simon Pallas in 1773 as a mouse. The species name sungorus derives from the Dsungaria. In 1778, Pallas renamed the Djungarian hamster to mouse songarus. Ned Hollister ordered the Djungarian hamster in 1912 to the genus Phodopus. A. I. Argiropulo, in 1933, changed the name to priority sungorus and united the Djungarian hamster as a subspecies of Phodopus sungorus sungorus with the Campbell's Dwarf Hamster.
Djungarian hamsters are often found on the pet market in Europe and North America. Care of the Djungarian hamster is similar to all other species of Phodopus. Djungarian hamsters, along with most rodents, are prone to tumours. They can also receive injury in the cheek pouch by sharp objects damaging the fragile inner lining. Other health problems include bite wounds, broken teeth, constipation, dehydration, dental malocclusion, diarrhea and ear problems. The Djungarian hamster is easy to tame. In addition to natural colourings in the wild, ("ruddy" or "agouti") Djungarian hamsters in captivity come in a variety of different colours.
Djungarian hamsters reproduce at a faster rate than Syrian hamsters. Phodopus are able to become pregnant again on the same day that they have given birth. This can all happen within a thirty-six day period. This is done as a survival strategy to produce large numbers of offspring in a short period of time. This places tremendous demands on the mother. Research suggests biparental care in Campbell's hamsters (Phodopus campbelli) but not in Djungarian hamsters (Phodopus sungorus). Frequent fighting can occur between the pups and as soon as they are weaned from their mother, they are separated from their mother. They should not be separated from their mother before three weeks of age. Most Djungarian hamster dwarf hamsters grow to 3 to 4" long. Djungarian hamsters breed all year round as there is no specific breeding season.
During the breeding time, the Djungarian hamster may become aggressive. After mating, the female may want to attack the male to protect her babies. The male will usually hide in holes or caves to escape from the vicious bite of the female Djungarian hamster. The Djungarian hamster's estrous cycle lasts four days, this means every four days, the female may accept the male back to breed again. This usually occurs when the darkness of the evening sets in. If a male and female Djungarian hamster are not housed together from a young age, it is difficult to tell if the female is willing to breed with the male.
Of the five species kept commonly as pets, only the Campbell's dwarf hamster and Djungarian hamsters are able to interbreed and produce live offspring or hybrids. Although hybrids make suitable pets, the breeding of hybrids and cloning can cause health and breathing problems. In addition, the widespread breeding and distribution of hybrids could threaten the existence of both pure species and subspecies of the ecosystem, resulting in only mongrels. Hybridizing causes each litter to become smaller and the young begin to form congenital problems.
The golden hamster or Syrian hamster, Mesocricetus auratus, is a member of the rodent subfamily Cricetinae, the hamsters. In the wild, they are now considered vulnerable. Their numbers have been declining due to loss of habitat caused by agriculture and deliberate destruction by humans. However, captive breeding programs are well established, and captive-bred golden hamsters are popularly kept as pets and used as scientific research animals.
The size of adult animals ranges from 5 to 7 in (13 to 18 cm) long, with a lifespan of two to three years. In captivity, the golden hamster is most active at night, but in the wild, it is a crepuscular animal. Wild hamsters sleep during the day in the deepest part of their burrows to avoid predators and wake up after sunset, being active on the ground for a few hours in the early and late parts of the night.
Like most members of the subfamily, the golden hamster has expandable cheek pouches, which extend from its cheeks to its shoulders. In the wild, hamsters are larder hoarders; they use their cheek pouches to transport food to their burrows. Their name in the local Arabic dialect where they were found translates to "mister saddlebags" (Arabic: أبو جراب) due to the amount of storage space in their cheek pouches.][ If food is plentiful, the hamster stores it in large amounts.
Sexually mature female hamsters come into season (oestrus) every four days. Golden hamsters have the shortest gestation period in any known placental mammal at only 16 days. Gestation has been known to last up to 18 days, but this is rare and almost always includes complications. They can produce large litters of 20 or more young, although the average litter size is between eight and ten pups. If a mother hamster is inexperienced or feels threatened, she may abandon or eat her pups. A female hamster enters estrous almost immediately after giving birth, and can become pregnant despite already having a litter. This puts stress on the mother's body and often results in very weak and undernourished young.
Hamsters are very territorial and intolerant of each other, with attacks against each other being ubiquitous. Exceptions do occur, usually when a female and male come together when the female is in heat, but even so, the female may attack the male after mating. Even brothers and sisters, once mature, may attack one another. In captivity, babies are separated from their mother and by gender after four weeks, as they sexually mature at four to five weeks old. Same-sex groups of siblings can stay with each other until they are about eight weeks old, at which point they will begin to become territorial and will fight with one another, sometimes to the death. Infanticide is not uncommon among female golden hamsters. In captivity they may kill and eat healthy young as a result of the pups interacting with humans, for any foreign scent is treated as a threat. Females will also eat their dead young in the wild to prevent predators detecting them.
Golden hamsters mark their burrows with secretions from special scent glands on their hips. Male hamsters in particular lick their bodies near the glands, creating damp spots on the fur, then drag their sides along objects to mark their territory. Females will also use bodily secretions and feces. The female and the male can have scent glands in different places. The female's is on the hip, and the male's can sometimes be found around the stomach area.
Golden hamsters originate from Syria and were found in 1839 by British zoologist George Robert Waterhouse. Their natural condition is a dry, hot desert climate. The widespread notion that the name hamster derives from the German for 'hoarding (food)' is wrong: rather, the German verb hamstern derives from the name of the animal, owing to their respective behavior. Hamster probably derives from the proto-Slavic chomẽstar (compare also with Russian 'хомячок', 'homyachok' or Polish 'chomik').
Waterhouse's original specimen was a female hamster—he named it Cricetus auratus or the "golden hamster". The skin of the specimen is kept at the British Museum of Natural History.
In 1930, Israel Aharoni, a zoologist and professor at the Hebrew University of Jerusalem, captured a mother hamster and her litter of pups in Aleppo, Syria. The hamsters were bred in Jerusalem as laboratory animals. Some escaped from the cage through a hole in the floor, and most of the wild golden hamsters in Israel today are believed to be descended from this litter.
Descendants of the captive hamsters were shipped to Britain in 1931, where they came under the care of the Wellcome Bureau of Scientific Research. They bred well and two more pairs were given to the Zoological Society of London in 1932. The descendants of these were passed on to private breeders in 1937. A separate stock of hamsters was exported from Syria to the USA in 1971, but apparently none of today's North American pets is descended from these (at least in the female line), because recent mitochondrial DNA studies have established that all domestic golden hamsters are descended from one female – probably the one captured in 1930 in Syria.
Since the species was named, the genus Cricetus has been subdivided and this species (together with several others) was separated into the genus Mesocricetus, leading to the currently accepted scientific name for the golden hamster of Mesocricetus auratus.][
Following Professor Aharoni's collection in 1930, only infrequent sightings and captures were reported in the wild. Finally, to confirm the current existence of the wild golden hamster in northern Syria and southern Turkey, two expeditions were carried out during September 1997 and March 1999. The researchers found and mapped 30 burrows. None of the inhabited burrows contained more than one adult. The team caught six females and seven males. One female was pregnant and gave birth to six pups. All these 19 caught golden hamsters, together with three wild individuals from the University of Aleppo, were shipped to Germany to form a new breeding stock.
Observations of females in this wild population have revealed, contrary to laboratory populations, activity patterns are crepuscular rather than nocturnal, possibly to avoid nocturnal predators such as owls.
Hamsters are widely used in research. For example, according to the Canadian Council for Animal Care, a total of 6,402 hamsters were used for research in 2006 in Canada, making them the fourth most popular rodent after mice (910,540), rats (331,560), and gerbils (37,246).
In captivity, golden hamsters follow well-defined daily routines of running in their hamster wheel, which has made them popular subjects in circadian rhythms research. For example, Michael Menaker used this behavior to provide definitive evidence that the suprachiasmatic nucleus is the source of mammalian circadian rhythms. They have a number of fixed action patterns that are readily observed, including scent-marking and body grooming, which is of interest in ethology (the study of animal behaviour).
By far, though, the greatest use of hamsters is in biomedical research. Among other things, because captive golden hamsters are highly inbred (being descended from only a few captured individuals), they have a high incidence of a genetic heart condition causing dilated cardiomyopathy. Several inbred strains of hamsters have been developed as animal models for human forms of dilated cardiomyopathy. The gene responsible for hamster cardiomyopathy in a widely studied inbred hamster strain, BIO14.6, has been identified as being delta-sarcoglycan. Pet hamsters are also potentially prone to cardiomyopathy, which is a not infrequent cause of unexpected sudden death in adolescent or young adult hamsters.
Syrian hamsters are also widely-used in research into alcoholism, by virtue of their large livers, and ability to metabolise high doses.
Scientific studies of animal welfare concerning captive golden hamsters have shown they prefer to use running wheels of large diameters (35 cm diameter was preferred over 23 cm, and 23 cm over 17.5 cm,), and that they prefer bedding material which allows them to build nests, if nesting material is not already available. They prefer lived-in bedding (up to two weeks old - longer durations were not tested) over new bedding, suggesting they may prefer bedding changes at two-week intervals rather than weekly or daily. They also prefer opaque tubes closed at one end, 15 cm in diameter, to use as shelter in which to nest and sleep.
The golden hamster can contract contagious reticulum cell sarcoma which can be transmitted from one golden hamster to another by means of the bite of the mosquito Aedes aegypti.
Golden hamsters are popular as house pets due to their docile, inquisitive nature, cuteness and small size. However, these animals have some special requirements that must be met for them to be happy and healthy. Although some people think of them as a pet for young children, the American Society for the Prevention of Cruelty to Animals recommends hamsters as pets only for people 10 years or older and the child should be supervised by an adult.][
Most hamsters in American and British pet stores are golden hamsters. Originally, golden hamsters came in just one color — the mixture of brown, black, and gold which gave them their "golden" name — but they have since developed a variety of color and pattern mutations, including cream, white, blonde, cinnamon, tortoiseshell, black, three different shades of gray, dominant spot, banded and dilute.
The Humane Society of the United States states no habitat is too big for a hamster. Cages should be as big as possible, safe, comfortable and interesting. Golden hamsters are energetic and need space to exercise.
"Angora" hamsters are commonly known as "teddy bear" hamsters. Females have short, velvety fur in many different colors. Male teddy bear hamsters usually have much longer fur than the female variety, culminating in a "skirt" of longer fur around their backsides.
Chinese striped hamster
Hamsters are rodents belonging to the subfamily Cricetinae. The subfamily contains about 25 species, classified in six or seven genera.
Hamsters are crepuscular and remain underground during the day to avoid being caught by predators. In the wild, they feed primarily on seeds, fruits, and vegetation, and will occasionally eat burrowing insects. They have elongated cheek pouches extending to their shoulders in which they carry food back to their burrows.
Hamster behavior varies depending on their environment, genetics, and interaction with people. Because they are easy to breed in captivity, hamsters are often used as laboratory animals. Hamsters have also become established as popular small house pets, and are sometimes accepted even in areas where other rodents are disliked, and their typically solitary nature can reduce the risk of excessive litters developing in households.
Although the Syrian hamster or golden hamster (Mesocricetus auratus) was first described scientifically in 1839, researchers were not able to successfully breed and domesticate hamsters until 1939. The entire laboratory and pet populations of Syrian hamsters appear to be descendants of a single brother-sister pairing. These littermates were captured and imported in 1930 from Aleppo [Syria] by Israel Aharoni, a zoologist of the University of Jerusalem. In Jerusalem, the hamsters bred very successfully. Years later, animals of this original breeding colony were exported to the USA, where Syrian hamsters became one of the most popular pets and laboratory animals. Comparative studies of domestic and wild Syrian hamsters have shown reduced genetic variability in the domestic strain. However, the differences in behavioral, chronobiological, morphometrical, hematological, and biochemical parameters are relatively small and fall into the expected range of interstrain variations in other laboratory animals.
In 1774, Friedrich Gabriel Sulzer, a companion of Johann-Wolfgang von Goethe, devoted a whole academic monograph in the domain of social sciences and natural history to hamsters, entitled "An approach to a natural history of the hamster" ("Versuch einer Naturgeschichte des Hamsters"). In several instances, he used the hamster to document the equal rights of all beings, including Homo sapiens.
The name "hamster" is a loanword from the German, which itself derives from earlier Old High German hamustro. It is possibly related to Old Russian choměstrǔ, which is either a blend of the root of Russian khomiak "hamster" and a Baltic word (cf. Lithuanian staras "hamster") or of Persian origin (cf. Av hamaēstar "oppressor").
Hamsters are typically stout-bodied, with tails shorter than body length, and have small, furry ears, short, stocky legs, and wide feet. They have thick, silky fur, which can be long or short, colored black, grey, honey, white, brown, yellow, red, or a mix, depending on the species. Two species of hamster belonging to the genus Phodopus, Campbell's dwarf hamster (P. campbelli) and the Djungarian hamster (P. sungorus), and two of the genus Cricetulus, the Chinese striped hamster (C. barabensis) and the Chinese hamster (C. griseus) have a dark stripe down their heads to their tails. The species of genus Phodopus are the smallest, with bodies 5.5 to 10.5 cm (2.2 to 4.1 in) long; the largest is the European hamster (Cricetus cricetus), measuring up to 34 cm (13.4 in) long, not including a short tail of up to 6 cm (2.4 in). The Angora hamster, also known as the long-haired or teddy bear hamster, which is a type of the golden hamster is the second-largest hamster breed, measuring up to 18 cm (7.1 in) long.
The hamster tail can be difficult to see, as it is usually not very long (about 1/6 the length of the body), with the exception of the Chinese dwarf hamster, which has a tail the same length as the body. One rodent characteristic that can be highly visible in hamsters is their sharp incisors; they have an upper pair and lower pair which grow continuously throughout life, so must be regularly worn down. Hamsters are very flexible, but their bones are somewhat fragile. They are extremely susceptible to rapid temperature changes and drafts, as well as extreme heat or cold.
Hamsters have poor eyesight; they are nearsighted and colorblind. To compensate for their poor sight when in unfamiliar territory, hamsters have scent glands on their flanks (and abdomens in Chinese and dwarf hamsters). A hamster rubs these areas of its body against various objects, and leaves a trail of smells to follow to return to its home den.][ Hamsters also use their sense of smell to identify pheromones and gender, and to locate food. They are also particularly sensitive to high-pitched noises and can hear and communicate in the ultrasonic range.
Hamsters are omnivores. Although they can survive on a diet of exclusively commercial hamster food, other items, such as vegetables, fruits, seeds, and nuts, can be given, but these should be removed before they become rotten. Hamsters in the Middle East have been known to hunt in packs to find insects for food. Hamsters are hindgut fermenters and must eat their own feces (coprophagy) to recover nutrients digested in the hindgut, but not absorbed.
A behavioral characteristic of hamsters is food hoarding. They carry food in their spacious cheek pouches to their underground storage chambers. When full, the cheeks can make their heads double, or even triple in size.
Most hamsters are strictly solitary. If housed together, acute and chronic stress may occur, and they may fight fiercely, sometimes fatally. Some dwarf hamster species may tolerate conspecifics. Russian hamsters form close, monogamous bonds with their mates, and if separated, they may become very depressed. This happens especially in males. Males will become inactive, eat more, and even show some behavioral changes similar to some types of depression in humans.][ This can even cause obesity in the hamster.
Evidence conflicts as to whether hamsters are crepuscular or nocturnal. Khunen writes, "Hamsters are nocturnal rodents who [sic] are active during the night...", but others have written that because hamsters live underground during most of the day, only leaving their burrows about an hour before sundown and then returning when it gets dark, their behavior is primarily crepuscular.][ Fritzsche indicated although some species have been observed to show more nocturnal activity than others, they are all primarily crepuscular.
Wild Syrian hamsters are true hibernators and allow their body temperature to fall close to ambient temperature (but not below 20°C). This kind of thermoregulation diminishes the metabolic rate to about 5% and helps the animal to considerably reduce the need for food during the winter. Hamsters may not hibernate per se, but instead reduce the rate of a number of physiological systems, such as breathing and heart rate, for short periods of time. These periods of torpor (defined as "a state of mental or physical inactivity or insensibility") can last up 10 days.][
All hamsters are excellent diggers, constructing burrows with one or more entrances, with galleries connected to chambers for nesting, food storage, and other activities. They use their fore- and hindlegs, as well as their snouts and teeth, for digging. In the wild, the burrow buffers extreme ambient temperatures, offers relatively stable climatic conditions, and protects against predators. Syrian hamsters dig their burrows generally at a depth of 0.7 m. A burrow includes a steep entrance pipe (4–5 cm in diameter), a nesting and a hoarding chamber and a blind-ending branch for urination. Laboratory hamsters have not lost their ability to dig burrows; in fact, they will do this with great vigor and skill if they are provided with the appropriate substrate.
Wild hamsters will also appropriate tunnels made by other mammals; the Djungarian hamster, for instance, uses paths and burrows of the pika.][
Hamsters become fertile at different ages depending on their species. Both Syrian and Russian hamsters mature quickly and can begin reproducing at a young age (4–5 wk), whereas Chinese hamsters will usually begin reproducing at two to three months of age, and Roborovskis at three to four months of age. The female’s reproductive life lasts about 18 months, but male hamsters remain fertile much longer. Females are in estrus about every four days, which is indicated by a reddening of genital areas, a musky smell, and a hissing, squeaking vocalisation she will emit if she believes a male is nearby.
When seen from above, a sexually mature female hamster has a trim tail line; a male's tail line bulges on both sides. This might not be very visible in all species. Male hamsters typically have very large testes in relation to their body size. Before sexual maturity occurs, it is more difficult to determine a young hamster's sex. When examined, female hamsters have their anal and genital openings close together, whereas males have these two holes farther apart (the penis is usually withdrawn into the coat and thus appears as a hole or pink pimple).
Hamsters are seasonal breeders and will produce several litters a year with several pups in each litter. The breeding season is from April to October in the Northern Hemisphere, with two to five litters of one to 13 young being born after a gestation period of 16 to 23 days. Gestation lasts 16 to 18 days for Syrian hamsters, 18 to 21 days for Russian hamsters, 21 to 23 days for Chinese hamsters and 23 to 30 for Roborovski hamsters. The average litter size for Syrian hamsters is about seven pups, but can be as great as 24, which is the maximum number of pups that can be contained in the uterus. Campbell's dwarf hamsters tend to have four to eight pups in a litter, but can have up to 13. Djungarian hamsters tend to have slightly smaller litters, as do Chinese and Roborovski hamsters.
Female Chinese and Syrian hamsters are known for being aggressive toward the male if kept together for too long after mating. In some cases, male hamsters can die after being attacked by the female. If breeding hamsters, separation of the pair after mating is recommended, or they will attack each other.
Female hamsters are also particularly sensitive to disturbances while giving birth, and may even eat their own young if they think they are in danger, although sometimes they are just carrying the pups in their cheek pouches. If captive female hamsters are left for extended periods (three weeks or more) with their litter, they may cannibalize the litter, so the litter must be removed by the time the young can feed and drink independently.
Hamsters are born hairless and blind in a nest the mother will have prepared in advance. After one week, they begin to explore outside the nest. They are completely weaned after three weeks, or four for Roborovski hamsters. Most breeders will sell the hamsters to shops when they are three to nine weeks old.
Syrian hamsters typically live no more than two to three years in captivity, and less in the wild. Russian hamsters (Campbell's and Djungarian) live about two to four years in captivity, and Chinese hamsters 2.5-3.0 yr. The smaller Roborovski hamster often lives to three years in captivity.
The best-known species of hamster is the golden or Syrian hamster (Mesocricetus auratus), which is the type most commonly kept as pets. It is also sometimes called a "fancy" hamster. Pet stores also have taken to calling them "honey bears", "panda bears", "black bears", "European black bears", "polar bears", "teddy bears", and "Dalmatian", depending on their coloration. Several variations, including long-haired varieties, grow hair several centimeters long and often require special care. British zoologist Leonard Goodwin claimed most hamsters kept in the United Kingdom were descended from the colony he introduced for medical research purposes during the Second World War.
Other hamsters kept as pets are the various species of "dwarf hamster". Campbell's dwarf hamster (Phodopus campbelli) is the most common—they are also sometimes called "Russian dwarfs"; however, many hamsters are from Russia, so this ambiguous name does not distinguish them from other species appropriately. The coat of the Djungarian or winter-white Russian dwarf hamster (Phodopus sungorus) turns almost white during winter (when the hours of daylight decrease). The Roborovski hamster (Phodopus roborovskii) is extremely small and fast, making it difficult to keep as a pet. The Chinese hamster (Cricetulus griseus), although not technically a true "dwarf hamster", is the only hamster with a prehensile tail (about 4 cm long)][—most hamsters have very short, nonprehensile tails.
Many breeders also show their hamsters, so breed towards producing a good, healthy, show hamster with a view to keeping one or two themselves, so quality and temperament are of vital importance when planning the breeding.
Taxonomists generally disagree about the most appropriate placement of the subfamily Cricetinae within the superfamily Muroidea. Some place it in a family Cricetidae that also includes voles, lemmings, and New World rats and mice; others group all these into a large family called Muridae. Their evolutionary history is recorded by 15 extinct fossil genera and extends back 11.2 million to 16.4 million years to the Middle Miocene Epoch in Europe and North Africa; in Asia it extends 6 million to 11 million years. Four of the seven living genera include extinct species. One extinct hamster of Cricetus, for example, lived in North Africa during the Middle Miocene, but the only extant member of that genus is the European or common hamster of Eurasia.
Neumann et al. (2006) conducted a molecular phylogenetic analysis of 12 of the above 17 species using DNA sequence from three genes: 12S rRNA, cytochrome b, and von Willebrand factor. They uncovered the following relationships:
The genus Phodopus was found to represent the earliest split among hamsters. Their analysis included both species. The results of another study suggest Cricetulus kamensis (and presumably the related C. alticola) might belong to either this Phodopus group or hold a similar basal position.
The genus Mesocricetus also forms a clade. Their analysis included all four species, with M. auratus and M. raddei forming one subclade and M. brandti and M. newtoni another.
The remaining genera of hamsters formed a third major clade. Two of the three sampled species within Cricetulus represent the earliest split. This clade contains C. barabensis (and presumably the related C. sokolovi) and C. longicaudatus.
The remaining clade contains members of Allocricetulus, Tscherskia, Cricetus, and C. migratorius. Allocricetulus and Cricetus were sister taxa. Cricetulus migratorius was their next closest relative, and Tscherskia was basal.
Some similar rodents sometimes called "hamsters" are not currently classified in the hamster subfamily Cricetinae. These include the maned hamster, or crested hamster, which is really the maned rat (Lophiomys imhausi). Others are the mouse-like hamsters (Calomyscus spp.), and the white-tailed rat (Mystromys albicaudatus).
A hamster called Rhino features in the 2008 animated film Bolt and the spin-off 2009 short film Super Rhino.
In "Tales of the Riverbank", narrated by Johnny Morris, the main character was Hammy the Hamster.
The Chinese striped hamster (Cricetulus barabensis), also known as the striped dwarf hamster, is a species of hamster. It is distributed across Northern Asia, from southern Siberia through Mongolia and northeastern China to northern North Korea. An adult Chinese striped hamster weighs 16.7-31.0g, and has a body length of 74.2-103.6 mm with a tail of 21-36 mm. It is smaller and has a much shorter tail than the greater long-tailed hamster, Tscherskia triton, which inhabits much of the same range.
There is quite some confusion over the Latin name of the Chinese striped hamster and the closely related Chinese hamster. Some people consider the Chinese hamster (Cricetulus griseus) and the Chinese striped hamster (Cricetulus barabensis) different species , whereas others classify them as identical , the Chinese striped hamster as a subspecies of the Chinese hamster (in which case the Latin name of the Chinese striped hamster would be Cricetulus griseus barabensis)  or the other way round (in which case the Latin name of the Chinese hamster would be Cricetulus barabensis griseus) .
Lab block is the specially formulated food fed to mice and rats kept in a laboratory. It is commonly accepted as providing all the necessary nutrients in appropriate quantity in order for the animals to remain healthy. The main ingredient in most block food is typically corn, followed by soy.
Campbell's dwarf hamster
The Ciscaucasian hamster (Mesocricetus raddei) is a species of rodent in the family Cricetidae. It is also known as the Georgian hamster and is found only in Georgia and Russia.
This hamster occurs on the northern slopes of the Caucasus and Ciscaucasia, between Dagestan, the Don River and the Sea of Azov. It is also known from a single record in Georgia. It appears to be extending its range north and north-westwards in its plains habitats but in the mountains the population remains stable. It is found in grassy steppes and also mountain steppes at elevations from 1600 to 2300 m above sea level. It favours pasture and cultivated land and also occurs in belts of trees and rough grass between fields but not in dense woodland.
Hamsters of the subspecies found in mountainous regions are larger than the ones found on the plains. They are about 28 cm (11 in) long with a short tail, 1.5 cm (0.59 in) long. They are yellowish-brown above with creamy-white throat and underparts and a black ventral region. There are two broad black stripes at the shoulder and the ears are large and rounded. This hamster is considered an agricultural pest. It is mainly nocturnal, emerging at dusk to feed on grasses and herbs in spring and early summer, and on seeds, crops and roots in the autumn. The burrow is extensive and has several exits in the mountain subspecies but only one on the plains. Large stores of food (up to 16 kg (35 lb)) are laid up in the autumn before hibernation which lasts for four to six months depending on the temperature and altitude. This food is mostly eaten in the spring upon emergence from hibernation. In the mountains there are two generations each year but on the plains there may be three or four. Litter size is up to twenty and averages about twelve. This fecundity means that the species can recover quickly after harsh winters and the population size is subject to considerable fluctuations.
In some years M. raddei becomes a considerable pest of agricultural crops. It can damage cereals and perennial grasses, disrupt potato plantings, melon fields and vegetable gardens. Close to the burrow the vegetation may be completely destroyed. It is sometimes trapped for its fur.
Campbell's dwarf hamster (Phodopus campbelli) is a species of hamster in the genus Phodopus. It was given its common name by Oldfield Thomas in honour of W.C. Campbell, who collected the first specimen in Mongolia on July 1, 1902. It is distinguished from the closely related Djungarian hamster as it has smaller ears and no dark fur on its crown. Campbell's dwarf hamster typically has a narrow dorsal stripe compared to the Djungarian hamster and grey fur on the stomach.
In the wild, the breeding season for Campbell's dwarf hamster varies by location. For example, the breeding season begins towards the middle of April in Tuva and towards the end of April in Mongolia. However, in captivity, there is no fixed breeding season and they can breed frequently throughout the year. Females are usually sexually mature at two months of age and the gestation period is typically 20 days. Campbell's dwarf hamster is crepuscular, along with all species of Phodopus and is active throughout the year. Campbell's dwarf hamsters are omnivores, and so feed on both plant and insect material. Campbell's dwarf hamster inhabits burrows with four to six horizontal and vertical tunnels in the steppes and semi deserts of central Asia, the Altai mountains, autonomous areas of Tuva and the Hebei province in northeastern China.
The golden hamster or Syrian hamster, Mesocricetus auratus, is a member of the rodent subfamily Cricetinae, the hamsters. In the wild, they are now considered vulnerable. Their numbers have been declining due to loss of habitat caused by agriculture and deliberate destruction by humans. However, captive breeding programs are well established, and captive-bred golden hamsters are popularly kept as pets and used as scientific research animals.
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In journalism, a human interest story is a feature story that discusses a person or people in an emotional way. It presents people and their problems, concerns, or achievements in a way that brings about interest, sympathy or motivation in the reader or viewer.
Human interest stories may be "the story behind the story" about an event, organization, or otherwise faceless historical happening, such as about the life of an individual soldier during wartime, an interview with a survivor of a natural disaster, a random act of kindness or profile of someone known for a career achievement.