Hamster

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Wikipedia:How to read a taxobox
How to read a taxobox
Hamsters
Fossil range: Middle Miocene - Recent
A dwarf hamster
A dwarf hamster
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Rodentia
Suborder: Myomorpha
Superfamily: Muroidea
Family: Cricetidae
Subfamily: Cricetinae
Fischer de Waldheim, 1817
Genera

Mesocricetus
Phodopus
Cricetus
Cricetulus
Allocricetulus
Cansumys
Tscherskia

A hamster is a rodent belonging to the subfamily Cricetinae. The subfamily contains about 18 species, classified in six or seven genera. Hamsters are indigenous to the Middle East and southeastern Europe. Because they are easy to keep and breed in captivity, hamsters are often used as lab animals and pets.


Contents

[edit] Species of hamster

The best known species of hamster is the Syrian or Golden Hamster (Mesocricetus auratus), which is the type of hamster most commonly kept as a pet. 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," and "Dalmatian," depending on their coloration. There are also several variations, including long-haired ones that grow hair several centimeters long and often require special care. Golden Hamsters will fight to the death if kept with others of their kind once mature, so an important rule of Golden Hamster keeping is "one hamster, one cage".

The best place always to buy a hamster is directly from a private or hobbyist breeder but this may not always be possible and therefore many hamster owners buy their first hamster from a pet shop. The advantages of buying from a private or hobbyist breeder is that breeding has usually been carefully planned and thought through with regard to producing robust, healthy hamsters of good temperament. Many breeders will also offer some form of guarantee contracting to take the hamster back if not suitable. Unfortunately the same cannot always be said for hamsters sold in pet shops or those that have come from commercial breeding farms where hamsters are bred in mass numbers for the pet market.

Many breeders also show their hamsters and so breed towards producing a good healthy show hamster with a view to keeping one or two themselves so quality and temperament is of vital importance when planning the breeding.Although breeders of show hamsters specialise in breeding show hamsters, there are also owners who have bred their pet hamsters. These may be the result of a planned or unplanned pregnancy but the hamsters have usually been well cared for and handled regularly and so make very suitable pets.Buying a hamster direct from the breeders means that there is the opportunity to see the parents and know the date of birth of the hamster(s) that it is intended to purchase.

Other hamsters that are kept as pets are four species of dwarf hamster. Campbell's Hamster (Phodopus campbelli) is the most common of the four—they are also sometimes called "Russian Dwarfs"; however, many hamsters originate in Russia, and so this name does not distinguish them. The coat of the Winter White Hamster (Phodopus sungorus) turns white during winter (when the hours of daylight decrease). The Roborovski Hamster (Phodopus roborovskii) is extremely small and fast. 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, non-prehensile tails.

[edit] Hamsters as pets

A Syrian or Golden Hamster, Mesocricetus auratus
A Syrian or Golden Hamster, Mesocricetus auratus

The care of all pet hamsters is fundamentally similar, but there are differences in feeding and housing needs. Dwarf hamsters are sociable and are best kept with a cagemate of the same gender to prevent loneliness, but Syrians are extremely territorial and will kill other hamsters in their cage. Chinese hamsters can be kept in pairs or groups but require a relatively large amount of cage space for them to live peaceably. Although Chinese hamsters are very placid in nature, female Chinese hamsters tend to become very aggressive towards any male cagemates when pregnant. Hamsters are nocturnal by nature and therefore unsuitable as pets for young children. Many people prefer them to rats as pets, given rats' generally unsavory popular reputation. Unlike rats, they are not particularly good at learning tricks but can be entertaining to play with and watch. They are also much smaller than guinea pigs and therefore more appropriate for homes with limited space.

In many countries, the Campbell's hamsters are more popular than the winter white, while the reverse holds for some countries in Europe. Roborovski and Chinese hamsters are somewhat more difficult to breed and keep, and are usually only available from breeders and large chain stores. They are the least common type of hamster to be kept as pets. Hamsters are popular pets all over the world, with the exception of Australia and New Zealand where their importation has been banned lest escaped pets form feral communities, interfere with the local ecology and become agricultural pests and a real problem.

[edit] Housing

Hamster house with wheel and water bottle
Hamster house with wheel and water bottle

Hamsters can be kept both in cages and in terrariums, both of which are available in pet stores. Cages are easier to carry, their bars can be used for climbing, and they usually include a convenient front door. On the other hand, glass boxes keep hamsters from throwing litter out of their cages, provide a better view into the hamster's home, and create a quieter and more sheltered interior. In general, terrariums are more appropriate for dwarf hamsters, which are more sensitive to a disquieting environment and which would otherwise need very narrow-grid bars to keep them from slipping through. Middle-sized hamsters, such as the Syrian Hamster, especially enjoy climbing the cage walls. Unfortunately they also love to nibble at the bars, which, bearing in mind that these are nocturnal animals, can be exceedingly annoying to their diurnal owners. Climbing can pose a hazard as the hamster can get its leg caught in the bars and fracture its leg. On the other hand, bars (the cage should have horizontal and vertical bars) are more open to the outside world; cages might be a better choice for these hamsters.

Despite the hamster's small size, appropriate housings should always have a floor space of at least two square feet and a strong top because hamsters are surprisingly good climbers. Glass boxes must not be higher than their width to allow for a sufficient air circulation. Although smaller in size, dwarf hamsters should have bigger housings than their larger relatives, at least 80 cm by 40 cm (2 feet by 4 feet). The reason for this is that the dwarfs are very active, running and digging a lot, but they often cannot be taken outside their houses for long, because they are not comfortable there and, due to their smaller size, are more endangered when leaving their domicile. Usually hamsters with a bigger and more interesting home will live longer and provide more visual entertainment.

In the case of self-built dwellings, care should be taken to avoid materials that are dangerous to the animals. Plywood and wood from conifers is not suitable, because hamsters gnaw at their houses and both glue and resin are poisonous for them. Using standard water-soluble white wood glue to join pieces of solid wood, such as birch or beech wood, creates a safe environment for the hamster, although it may still chew through the wood. A purchased cage can be equipped with several intermediate levels, connected using stairs. Using wire grid for these platforms instead of solid wood causes serious injuries and is therefore not recommended.

date=April 2007}} Some plastic tubes are poorly ventilated, which leads to concentration of moisture and methane, causing respiratory illnesses and occasionally even suffocation. Some tubes are better ventilated and many hamsters have no trouble with them.
date=April 2007}} Some plastic tubes are poorly ventilated, which leads to concentration of moisture and methane, causing respiratory illnesses and occasionally even suffocation. Some tubes are better ventilated and many hamsters have no trouble with them.
A young hamster playing with a toy house.
A young hamster playing with a toy house.

The most desirable place for the hamster's home is a well-lit room of constant, moderate temperature (18 to 26°C, 64 to 80°F), in a place out of strong sunlight that could cause dangerous heating. It is also important to avoid drafts -- especially when wire cages are used. Though they cannot see very far, hamsters become more relaxed and curious when positioned somewhat above the ground (at least 65 cm (2 feet)), from where they can perceive their surroundings.

The floors of the hamster's residence should be covered, including all intermediate levels, with a sufficiently thick layer of litter for rodents. Many types of litter are available in pet stores. Although many materials may work well, some commonly-used materials do not. Cat litter is dangerous, because gnawing and eating the chunks is deadly; Paper-based cat litter such as Newspaper is safe, though. Cedar, pine, and any other softwood-based litters or beddings contain aromatic oils (phenols), which can irritate a hamster's respiratory system, liver, and skin. One safe wood litter is aspen shavings. Also, litter made from recycled paper pulp works well to absorb odors and is safe for hamsters. These paper litters have had the inks and other chemicals washed out. Carefresh and Megazorb are both examples of safe beddings.

Hamsters are nest builders and a steady supply of fresh strips of tissue or newspaper (with soy-based ink) allows them to build a secure and comfortable spot in a corner of their enclosure or in their hiding house. Hay, from shops or even fresh from the garden, is also a valuable building material for cozy hamster nests, but is discouraged unless guaranteed to be pesticide-free. Hay also poses a risk of having some sharp pieces that could cut or scratch the hamster, causing an abcess.

Hamster bedding materials made of fluffy cotton cloth are extremely dangerous, as they can tangle around the hamster's neck and limbs as well as pose a choking hazard. If swallowed, they cannot be broken down by the hamster's digestive system.

A sand bath can provide hamsters with entertainment and help them groom. In the desert (their natural habitat) hamsters will roll around in the sand, which cleans their coats and prevents them from getting too oily. Dwarf hamsters in particular enjoy this activity. A sand bath can be made by filling a dish with clean sand. It is important to use a dish that will not tip over. Heavy ceramic and metal dishes are preferred. Chinchilla sand is often available in pet stores and can be used for hamsters, but sand that is powdery or dusty should be avoided as it will pose a hazard to a hamster's respiratory system.

Regular cleaning of a hamster's home is crucial for the hamster's health. The home must be cleaned at least once a week by replacing the soiled bedding where necessary. Hamsters are fairly neat in their bathroom habits if their enclosure is regularly cleaned. They choose one small location in which to urinate and defecate, making cleaning simple. The cages of dwarf hamsters may require slightly less-frequent cleaning (perhaps once every two weeks), and may have many (usually hidden) places used as toilets. It is not necessary to use harsh chemicals, warm soapy water is quite adequate. Hamsters orient themselves by the sense of smell. It is important therefore when cleaning the cage to leave some of the old bedding/nesting material so when the hamster is returned to the cage it recognises it is "home". Failure to do this will disorient the hamster and cause unnecessary distress. Harsh disinfectants need never be used to clean hamster homes, except in cases of illness (especially "wet tail" diarrhoea). It is worth adding that a suitable spare home or travel container/cage will come in handy, especially for the social dwarf species. A sick individual can conveniently be quarantined in this and the risk of passing infection to his or her housemates vastly reduced.

Another important component of a hamster's home is a hiding place where the animal can rest during the day. Not all commercially available houses are adequate. The houses should be of sufficient size and be closed on at least two sides. The same building materials are appropriate for these as for the actual cages. Even a small cardboard box with no ink (or only nontoxic ink) will work although it will have to be regularly replaced. Some houses add features such as a removable roof that helps to take away collected food (especially perishable items).

Syrian hamsters are solitary animals and have to be kept alone once they are mature (around 7 weeks and above). Dwarf hamsters are social and are best kept with another house mate but should be introduced at a young age. While two or more animals can live peacefully within one home if introduced at a young age, there can be exceptions where serious physical fighting occur and in such cases they should be separated as soon as blood is shed. In their natural habitat, there is substantially more empty space so that each hamster can have its own large territory. If more than one hamster is to live in a cage, then the cage must be larger (at least 40cm x 40cm per hamster) and there must be separate hiding houses for each animal. In any case, even after a long period of peaceful coexistence or even mating, there can be violent biting. In this situation, the hamsters should be separated immediately. Note also that, if a male and female hamster live together without fighting, they will usually reproduce rapidly and cause more space problems.

Hamsters (Syrians especially) are expert escape artists. A cage with loose bars should never be used as the hamsters will pull at these until they can squeeze through and make a dash for freedom. If a hamster does escape, the rule is not to panic. Close doors and conduct a thorough search. If the hamster doesn't show up, leave the cage open and accessible. Most often, hamsters will return to their cages within a day due to fatigue and hunger.

[edit] Gnawing

A roborovski dwarf hamster
A roborovski dwarf hamster

Despite their cuddly appearance, hamsters have long, thin, sharp teeth that can pierce a finger that is mistaken for a carrot or for a predator. When they are accustomed to being handled and are not startled, however, they are not inclined to bite and can be placed in the custody of responsible school-age children. Like many rodents, their teeth grow continuously and they must have appropriate things to chew on to relieve their instinctive gnawing and to help keep the teeth at a healthy length. They will gnaw on whatever is available, so they must be kept in enclosures that they cannot chew through. When the hamster is kept in or near a bedroom, their nocturnal nature combined with their gnawing habit can become distracting.

[edit] Exercise and entertainment

Like all pets, hamsters need exercise and entertainment to maintain their physical and mental health. An exercise wheel allows hamsters to run full speed to their hearts' content, and is a must, but it should be appropriate for the hamster's small size. Many commercial exercise wheels marketed for hamsters are made with wire rungs that can allow a hamster to slip and fall. Many authorities recommend solid plastic wheels as these eliminate the risk of injury by getting their head or foot stuck in one of the holes. When given the choice, however, both Syrian and dwarf hamsters do seem to prefer running on wire wheels, which spin more quickly. If a wheel is squeaking, a drop of cooking oil will often cause the squeaking to stop. In addition to a wheel, tubes and toys can provide your hamster opportunities to explore and play. For example, hamsters enjoy wooden tubes that somewhat mimic the burrows that they might have in the wild and allow their owners to enjoy their activities. (Be sure that whatever is placed in the hamster's cage is either bite proof or safe for the hamster to chew on.) Plastic "maze" tubes are popular, but if you choose to purchase some you should choose a brand that has air holes at frequent intervals to allow moisture and air to escape.

A hamster wheel. If the hamster has its back curved as in this picture, it needs a bigger wheel.
A hamster wheel. If the hamster has its back curved as in this picture, it needs a bigger wheel.

Clear plastic hamster balls or cars are available, into which the hamster is placed and then, by its own action, explores an entire house or yard. Hamster cars are not recommended because the hamster's movement is restricted by the shape of the car and this may cause stress or confuse them. In addition, make sure the ball is large enough - while a 5" (12-13 cm) ball may be large enough for dwarf hamsters, Syrians need a 9" or 10" (27-30 cm) diameter ball in order to feel comfortable. Use these toys only under supervision and use common sense. Unsupervised hamsters in these toys can become trapped against furniture and panic or they can roll downstairs, injuring themselves. Many experts advise against these toys due to the high danger of the hamster getting injured or frightened. Hamsters dislike round environments because they find their bearings using corners, and therefore may find balls uncomfortable.[citation needed] If they are used, do not leave them in these toys for extended periods, especially on warm days, and make sure to remove them frequently and allow them access to water or fresh fruits or vegetables. Toys should always allow the hamster to explore and use them at its own will, without forcing or violence. They should only be left in a hamster ball for 10-15 minutes at the most or they can dehydrate.

If they are handled frequently, hamsters enjoy being out of their enclosures and having the opportunity to explore. They can also become very tame if handled frequently. Syrian hamsters will be tame for life once they are tamed.

They must be kept away from holes in the wall or in large pieces of furniture, because they will seek out the dark and burrow-like confines of those areas and it can be difficult or impossible to convince them to come out again. Ceramic toys are fun and gnaw resistant, so they are a good choice.

Some hamsters love to dig, so a deep layer of sawdust in their cage will keep them occupied and thoroughly happy.

Finally, some books recommend providing a sand bath for your hamster, but not all hamsters seem to enjoy this (see housing for more information).

[edit] Food

Pet stores can provide basic food for hamsters that provides their nutritional needs, but they also enjoy fresh vegetables and fruits, bird seed, and even living insects like grasshoppers, which make up an important part of their natural diet. However, not all foods are suitable for hamsters and some, such as sweets made for humans or poisonous plants like the leaves of the tomato or rhubarb, may be most dangerous for the hamster's health. There are many myths regarding unsafe foods including that feeding lettuce causes wet tail and citrus fruits being toxic - both of which are untrue. Lettuce however has very little nutritional value and in excess can cause liver problems, and some hamsters may not like the taste of citrus fruits but they are safe to feed and hamsters have been observed in orange groves in the wild. Campbells dwarf hamsters are susceptible to hereditary diabetes, and any hamster suffering from diabetes should not have high sugar foods, such as fruits and corn. Although diabetes is not so common in other dwarf breeds, sugary commercial treats are best avoided as they are generally unhealthy and fattening. Like with most other animals (and humans), it is not true that hamsters can decide which food is good for them and they won't usually eat anything that is offered.

Hamsters should also always have fresh water available. Appropriate drinking devices can be found in stores. Being small animals that are adapted to the life in arid environments, hamsters can also ingest all necessary liquid via sufficient amounts of watery vegetables, such as cucumber, without any negative effects. However, providing water is usually more convenient and can be an easy way to add medication or vitamins to the hamster's diet, although vitamin drops on food or in water tend to be ineffective. Both water and vegetables must be fresh and have to be exchanged frequently, usually once a day. Water must not be given in open jars, since it is likely to be polluted and because wetness is generally very unhealthy for hamsters (they clean themselves very carefully without the need of additional water).

In detail, the solid food components can be divided into three categories: dry, fresh, and animal food. Dry food makes up the bulk of a hamster's diet. Besides the standard rodent food sold in pet stores, most other kinds of seeds, kernels, and nuts can be given. Care should be taken to limit the amount of fat contained within the diet. Especially sunflower seeds, nuts, and sesame are the most nutritious and are to be considered as a treat rather than as basic food. All kinds of grain, rice, noodles (dry), dry peas and lentils on the other hand can be provided more readily: about 120 g for a medium hamster and, depending on size, half the amount for a dwarf hamster is sufficient. Bread and similar bakery products contain many ingredients (e.g. yeast) that can trouble the hamster's digestion system. They should be given in small amounts for gnawing or be replaced by special wafers as found in pet stores. All dry food should be appropriate in size. Especially small hamsters often cannot cope well with large seeds, even if they are sold under the label "hamster food". Bird food like millet is a noteworthy alternative for small hamsters.

Hay, although a popular choice as it is cheap and easy to find, should not be fed to hamsters as it can cause damage to their sensitive cheek pouches, although sometimes people use a certain type of hay called "Timothy hay" which is still not very good for a hamster.

Fresh food is also an important part of the hamster's diet. As mentioned above, cucumber is a good supplement of water. Fresh carrot, spinach, broccolli, turnip, parsley, leaves and even branches of (non-poisonous) plants are also no problem in general. As mentioned previously lettuce is low in nutritional value. In addition, no conifer wood must be fed since resin is poisonous for hamsters. Hamsters are known to appreciate Tofu. In smaller amounts, grown hamsters also appreciate apple, pear, sweet paprika, banana, mango, grape, and strawberry. Too many sweet fruits on the other hand are not healthy. All kinds of cabbage should be avoided, since they may cause flatulence, which is quite dangerous for the hamster's sensitive digestion system. It is also dangerous to feed a hamster raw potatoes or potato tops, raw kidney beans, raw rhubarb or rhubarb leaves.

All hamsters should be given a more conservative diet. If accepted, herbs can also help to strengthen the hamster's health, though they cannot replace a veterinarian in case of a disease. Daisies (the flowers, not the stems or leaves) and dandelions are likewise appreciated. Plants used for hamster foods should never be placed near open windows because hamsters are more sensitive to chemical pollutions, due to their small body weight.

Finally, animal food is a major component of some hamsters' natural food. As pets, a large part of this can be replaced by dry food. Still, hamsters need some animal proteins for their health. While some people like to provide living insects from pet stores to their hamsters (mealworms are very suitable), others will prefer to give them dry dog biscuits. Some hamsters are known to accept yoghurt (yogurt) (natural, without sweet ingredients) or soft cheese (low fat, not too salty), and in any case egg noodles are usually taken gratefully. Syrian and dwarf hamsters will gratefully accept roast chicken bones with a little meat remaining. They seem particularly to enjoy gnawing the gristly joints of chicken drumsticks. If (dry or soft) dog or cat food is given, then the fat content has to be checked carefully. Furthermore, it must not contain molasses, which would harm the hamster.

It might be noted that many hamsters tend to carry away food from their food source (by carrying it in their cheek pouches) and hoard it away in a cache hidden somewhere inside their container. These caches, when combined with hamster urine or a leaky water source and poor airflow, can grow mold or start to rot, creating a hazardous environment for the hamster. To keep this from happening, clean hamster cages frequently.

There are also many foods that a hamster should never eat. This includes all kinds of human sweets, such as chocolate or candy, which are unhealthy and even dangerous. Furthermore, poisonous plants (also check indoor plants if the hamster is taken outside its housing) constitute a considerable danger. The various unhealthy and chemically treated products usually consumed by humans can cause problems. Salty foods should not be offered to hamsters. Other foods such as garlic, onions and pickles should also be avoided.

Campbell's dwarf hamsters are especially sensitive to Diabetes mellitus, and other dwarf hamster species may be somewhat sensitive too. Diabetes mellitus in hamsters is hereditry and not caused by the feeding of too much sugary foods. However, food and snacks containing molasses, honey, sugar, fruit sugar or other sweet stuff should be limited to small snacks as it can be fattening. Even with golden hamsters it may be useful to follow these guideline in order to avoid overweight and digestion disturbances.

[edit] Sex and longevity

Syrian hamsters typically live no more than two to three years in captivity, less than that in the wild. Russian Hamsters (Campbell's and Winter White) live approximately 1.5 to 2 years in captivity and Chinese Hamsters 2.5 to 3 years. The smaller Roborovski Hamster often lives to 3 to 3.5 years in captivity. Both Syrian and Russian hamsters mature quickly and can begin reproducing at a young age (4-5 weeks), whereas Chinese hamsters will usually begin reproducing at 2-3 months of age, and Roborovskis at 3-4 months of age. Breeding at a very young age is unhealthy for the female particularly in the case of the Syrian hamster and so females are best not mated until 4-6 months of age once they are fully mature. Left to their own devices, hamsters will produce several litters a year with several babies in each litter. Male and female hamsters are therefore usually kept in separate enclosures to prevent the addition of unwanted offspring.

After a female hamster mates, there is a gestation period of 16-18 days for Syrian hamsters, 18-21 days for the Russian hamsters, 21-23 days for Chinese hamsters and 23-30 for Roborovski hamsters before the female gives birth. If the mother-to-be is a dwarf hamster, she will sometimes drive the male away from the nest when the birth is about to occur. This is normal, and he will be permitted to come back once the pups are a little older. In the case of Syrian hamsters, the male will not take part in raising the young as they are kept separately. However, dwarf males will often assist the mother, bringing her food, sitting on the nest to keep it warm, and tracking down wayward young. The average litter for Syrians is about 7, but can be as great as 24, which is the maximum number of pups that can be contained in the womb. Campbell's Russian hamsters tend to have 4-8 in a litter but can have up to 14, Winter White Russian hamsters tend to have slightly smaller litters, as do the Chinese and Roborovski hamsters. The mother hamster will gather all the pups into a nest which it built. They will be hairless, have closed eyes, nurse from their mother, and move very little. After about a week, they will begin to wander from the nest and eat solid food. After a total of three weeks, the pups will be weaned and can leave the nest for good, except for Roborovski hamsters who mature at a slower rate and should not be removed from the mother until 4 weeks of age. They should be separated by sex at this time. One thing to watch out for while Syrian hamsters are mating, is that the female doesn't attack the male. If the female is not fully in season or if the male is introduced to the female on her territory she will attack and hurt the male hamster, so they must be separated. Hamster owners must make sure that all food has been removed from the cage so the two do not fight over it, and the hamsters are introduced either in the male's cage or on neutral territory and be prepared to separate quickly should a fight break out.

When seen from above, a sexually mature female hamster has a trim tail line; a male's tail line bulges on both sides. Male hamsters typically have very large testes in relation to their body size. Before sexual maturity occurs at about 4-6 weeks, young hamsters are harder to sex. When examined, female hamsters have two holes close together whereas males have anal and genital openings further apart than the female's (the member is usually withdrawn into the coat and thus appears as a hole or pink pimple).

[edit] Classification of hamsters

Taxonomists currently 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.

  • Subfamily Cricetinae
    • Genus Mesocricetus - Golden hamsters
      • Syrian hamster (Mesocricetus auratus); also called the Golden hamster or Teddy Bear hamster.
      • Turkish hamster (Mesocricetus brandti); also called Brandt's hamster, Azerbajaini hamster
      • Georgian Hamster (Mesocricetus raddei); also Ciscaucasian Hamster
      • Romanian Hamster (Mesocricetus newtoni)
    • Genus Phodopus - Dwarf hamsters
    • Genus Cricetus
      • European Hamster (Cricetus cricetus); also called the Common Hamster or Black-bellied Field Hamster
    • Genus Cricetulus
      • Ladak Hamster (Cricetulus alticola)
      • Striped Dwarf Hamster (Cricetulus barabensis including "C. pseudogriseus" and "C. obscurus"); also Chinese striped hamster, Chinese hamster
      • Chinese Hamster (Cricetulus griseus)
      • Tibetan Hamster (Cricetulus kamensis)
      • Long-tailed Hamster (Cricetulus longicaudatus)
      • Armenian Hamster (Cricetulus migratorius); also called the Migratory Grey Hamster, Grey Hamster, Grey Dwarf Hamster, or Migratory Hamster
      • Sokolov's Hamster (Cricetulus sokolovi)
    • Genus Allocricetulus
      • Mongolian Hamster (Allocricetulus curtatus)
      • Kazakh Hamster (Allocricetulus eversmanni); also Eversmann's Hamster
    • Genus Cansumys
      • Gansu Hamster (Cansumys canus)
    • Genus Tscherskia

[edit] Relationships among hamsters

Neumann et al. (2006) conducted a molecular phylogenetic analysis of 12 of the above 17 species of hamster using DNA sequence from three genes: 12S rRNA, cytochrome b, and von Willebrand factor. They uncovered the following relationships:

[edit] Phodopus group

The genus Phodopus was found to represent the earliest split among hamsters. Their analysis included both species. The results of another study (Lebedev et al., 2003) may suggest that Cricetulus kamensis (and presumably the related C. alticola) might belong to either this Phodopus group or hold a similar basal position.

[edit] Mesocricetus group

The genus Mesocricetus also formed a clade. Their analysis included all four species, with M. auratus and M. raddei forming one subclade and M. brandti and M. newtoni another.

[edit] Remaining genera

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 Cricetulus barabensis (and presumably the related C. sokolovi) and Cricetulus longicaudatus.

The remaining clade contains members of Allocricetulus, Tscherskia, Cricetus, and Cricetulus migratorius. Allocricetulus and Cricetus were sister taxa. Cricetulus migratorius was their next closest relative, and Tscherskia was basal.

[edit] Similar animals

Note that there are some rodents which are sometimes called "hamsters" that 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), although not nearly as marketable under that name. Others are the mouse-like hamsters (Calomyscus spp.), and the white-tailed rat (Mystromys albicaudatus).


[edit] References

  • Lebedev, V. S., N. V. Ivanova, N. K. Pavlova, and A. B. Poltoraus. 2003. Molecular phylogeny of the Palearctic hamsters. In Proceedings of the International Conference Devoted to the 90th Anniversary of Prof. I. M. Gromov on Systematics, Phylogeny and Paleontology of Small Mammals (A. Averianov and N. Abramson eds.). St. Petersburg.
  • Musser, G. G. and M. D. Carleton. 2005. Superfamily Muroidea. In Mammal Species of the World a Taxonomic and Geographic Reference (D. E. Wilson and D. M. Reeder eds.). Johns Hopkins University Press, Baltimore.
  • Neumann, K., J. Michaux, V. Lebedev, N. Yigit, E. Colak, N. Ivanova, A. Poltoraus, A. Surov, G. Markov, S. Maak, S. Neumann, R. Gattermann. 2006. Molecular phylogeny of the Cricetinae subfamily based on the mitochondrial cytochrome b and 12S rRNA genes and the nuclear vWF gene. Molecular Phylogenetics and Evolution, in press; Available online 17 February 2006.

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