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Djungarian hamster and/or Siberian hamster: who is who?

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Reprinted from European Pineal Society NEWS, 1998, number 38 (April): 7-11
DJUNGARIAN HAMSTER AND/OR SIBERIAN HAMSTER:
WHO IS WHO?
Stephan Steinlechner
Department of Zoology, School of Veterinary Medicine, D-30559 Hannover, Germany
Email: Stephan.Steinlechner@tiho-hannover.de
Colleagues keep asking me about the correct common name of Phodopus
sungorus. Is it the Djungarian hamster or the Siberian hamster or the Striped
hairy-footed hamster? And what about Phodopus campbelli, is it the Djungarian
hamster or Campbell's hamster, or what? In fact, there is considerable confusion
also in the literature concerning the common names for two of the now
recognized three main species of the genus Phodopus, namely Phodopus
sungorus (Pallas, 1773) and Phodopus campbelli (Thomas, 1905). The third
species, Phodopus roborovski (Satunin, 1903), the ”Desert hamster”, is rarely
used as a laboratory animal and is so different in its habitus from the two other
Phodopus species that it cannot be mistaken (Ross 1994). In contrast, P.
sungorus and P. campbelli are looking very similar to the unexperienced eye
and I have visited several labs where colleagues claimed to have a colony of P.
sungorus but instead it turned out to be P. campbelli. And in publications - even
from the same laboratory - one can find both common names ”Djungarian
hamster” and ”Siberian hamster” for P. sungorus as well as for P. campbelli.
In the late 1960s a Chech scientist, Dr. Figala, came to the laboratory of Prof.
Aschoff at the Max-Planck-Institute Andechs (Germany) on a ”von Humboldt
stipend”. He brought with him two breeding pairs of Phodopus sungorus,
started a colony and in collaboration with Goldau and Klaus Hoffmann made
initial observations on seasonal changes in body weight, fur color and the
occurrence of torpor in this dwarf hamster (Figala et al. 1968). Dr. Klaus
Hoffmann soon realized the great potential of Phodopus and he deserves the
merits of having introduced this hamster species as a very valuable animal
model for pineal research (for a review see Steinlechner and Niklowitz 1992).
Dr. Hoffmann was generous enough to give hamsters away to colleagues and by
1980 there were many laboratories all over the world working with Phodopus
from Hoffmann's stock or other sources.
At the time Klaus Hoffmann started his work Phodopus sungorus was
considered to exist in two different geographical races: the nominate form of
Phodopus sungorus sungorus, a north-western subspecies which turns white in
winter, and Phodopus sungorus campbelli in the south-east of the distrubution
range which does not change its fur color in winter (Argyropulo 1933,
Veselovski and Grundova 1964, Flint 1966). The generic name Phodopus was
8
introduced by Miller (1910) and is derived from phodos, the genitive case of the
Greek phos, meaning blister, and the Greek pous, meaning foot. It refers to the
large coalesced pad on the plantar surface of each foot (Ross, 1994, 1995). The
species name given by Pallas (1773) refers to the region ”Sungaria” (different
spellings exist: Dsungaria or Djungaria or Zungaria, see map), south of the
Altai mountains. The literal translation of the nominate form therefore is: ”the
blister-footed (D)Sungarian (hamster)”. Since Hoffmann clearly worked with
the nominate form, he consequently called it (as did most others before him,
e.g.Veselovski and Grundova 1964, Flint 1966) the Djungarian hamster. The
alternative name existing in the (English) literature at that time was the ”Hairy-
footed hamster” (Ellerman and Morrison-Scott, 1951). Never (at least to my
knowledge) was it called the ”Siberian hamster”. The other subspecies P.
sungorus campbelli was named in honour of W.C. Campbell, who collected the
type specimen in Inner Mongolia in 1902 (Ross 1995).
Already back in 1967 Vorontsov et al. reported differences in chromosome
morphology of both hamsters and in 1979 Yudin et al. showed that cross
breeding produced sterile male offspring (however, female offspring often is
fertil, Stetson, pers. comm.). These papers by Vorontsov et al. and Yudin et al.
were written in Russian and hence did not receive due attention for a long time.
Phodopus campbelli received its present taxonomic status as a separate species
in 1984 (Corbet, 1984). All those who worked with both species of Phodopus
will certainly agree that there are major behavioral and morphological
differences meriting the separation. Dr. K.W. Wynne-Edwards sucessfully
trapped both hamster species in the (at that time, i.e. early 1980s) U.S.S.R. and
worked with both species in the field as well as in the lab. To my kowledge,
Wynne-Edwards and Lisk (1984, 1987) were the first to name Phodopus
sungorus the Siberian hamster and Phodopus campbelli the Djungarian hamster.
Subsequently, many (especially American) colleagues and even the American
Society of Mammalogists (see Ross 1995) and the British Museum of Natural
History (Corbet and Hill, 1986) followed this suggestion. Although there are no
strikt rules for nomenclature for common names, this choice for the common
names is in my view very unfortunate and has led to the present major
confusion. Admittedly, Phodopus campbelli has its center of distribution south-
east of the Altai mountains (Region of Djungaria) but especially Mongolia,
whereas Phodopus sungorus originates from south-west Siberia and north-east
Kazakstan, making the common names quite logic. Even more logic would have
been ”Mongolian hamster” for P. campbelli and ”Kasak hamster” for P.
sungorus if the type locality (see below) played a role. On the other hand, I
think it is terribly misleading that a former subspecies is now called by the
common name of the nominate form. I am convinced that it would have avoided
confusion if the nominate form Phodopus sungorus had retained its original
common name, i.e. Djungarian hamster. It is the newly acknowledged species
9
which should get a new name. Another logic name would have been
”Campbell's hamster”. I have used the common name Djungarian hamster for
Phodopus sungorus in all my publications since 1977 and I see no good reason
to change this habit.
As I said before, there are no strikt rules for the use of common names,
however, there are indeed strikt rules for the use of scientific names. No editor
should accept papers in which only the common name is given. The use of only
the common names has led to misunderstandings, misinterpretations and even
awful mistakes. Therefore, I can only higly recommend, and in fact urge, all
colleagues to use the scientific name which designates the species beyond all
doubt. This requires of course that you know for sure which species you are
working with. The following short characterization of both species may help to
achieve this certainty:
Fig. 1: Map of Inner Asia showing the home land of Phodopus sungorus and
Phodopus campbelli (details and names see text). Adapted from Ellermann and
Morrison-Scott (1951).
10
Phodopus sungorus:
This is the preferred species for studies on circadian and seasonal rhythms and
for pineal research! During summer (i.e. long photoperiod), the pelage of P.
sungorus is dark greyish brown on the back and head with a black mid-dorsal
stripe. The fur on the underside is whitish to light grey. In winter (short
photoperiod) P. sungorus turns more or less completely white, except for the
mid-dorsal stripe. This color change is by far the best diagnosis of P. sungorus.
Body mass: in summer 35 g - 45 g, in winter 25 g - 30 g
Distribution: E. Kazakstan and S.W. Siberia, the Baraba Steppe (see map).
Type Locality: E. Kazakstan, 100 km west of Semipalatinsk, near Grachevsk.
Phodopus campbelli:
Similar size as P. sungorus. Pelage more dark brown as compared to P.
sungorus and underside slate grey. A suffusion of yellow or buffy on the
dividing line between the dorsal and ventral pelage. Mid-dorsal stripe narrower
and more sharply defined (see Ross 1995, for a complete description). No color
change in winter (short photoperiod)! Usually more aggressive than P.
sungorus.
Distribution: Steppes and semi-deserts of central Asia: Altai Mountains, Region
of Tuva, Transbaikalia, Mongolia.
Type Locality: ”Shaborte” N.E. Mongolia (about 42°40' N; 116°20' E). The
reported coordinates are approximate and vary between authors because
”Shaborte” is not a geographic locality but a Mongolian name for a mud
lake that dries out periodically (Argyropulo, 1933).
References:
Argyropulo AJ (1933). Die Gattungen und Arten der Hamster (Cricetinae
MURRAY, 1866) der Paläarktik. Zeitschrift für Säugetierkunde 8: 129-149.
Corbet, GB (1984). The mammals of the Paläarctic region: a taxonimic review.
Supplement. British Museum (Natural History), London, 45 pp.
Ellermann JR, Morrison-Scott TCS (1951). Checklist of Paläarctic and Indian
mammals 1758-1946. British Museum (Natural History), London, pp. 627-
628.
Figala J, Hoffmann K, Goldau G (1973). Zur Jahresperiodik beim
Dsungarischen Zwerghamster, Phodopus sungorus Pallas. Oecologia 12:89-
118.
Flint WE (1966). Die Zwerghamster der Paläarktischen Fauna. A. Ziemsen
Verlag, Wittenberg Lutherstadt, 97 pp.
11
Miller G (1910). Two new genera of murine rodents. Washington DC
Smithsonian Instiute Misc. Collect. 52:498.
Pallas P (1773) Reise durch verschiedene Provinzen des Russischen Reichs 2
(8): 703.
Ross PD (1994) Phodopus roborovskii. Am. Soc. Mammol., Mammalian
Species No. 459: 1-4.
Ross PD (1995) Phodopus campbelli. Am. Soc. Mammol., Mammalian Species
No. 503: 1-7.
Satunin KA (1903). Neue Nagetiere aus Zentralasien. Annuaire du Musée
zoologique de l'Academie impériale de St. Petersbourg 7:571-547.
Steinlechner S and Niklowitz P (1992). The impact of photoperiod and
melatonin on reproduction in small mammals. Animal Reprod. Sci. 30:1-28.
Thomas O (1905). A new Cricetulus from Mongolia. Annals and Magazine of
Natural History 6:322-323.
Veselovsky Z. and Grundová S. (1964). Beitrag zur Kenntnis des Dschungar-
Hamsters, Phodopus sungorus (Pallas, 1773). Zeitschrift für Säugetierkunde
30: 305-311.
Vorontsov NN, Radzhabli SJ and Lyapunova KL (1967) Karyological
differentiation of allopatric forms of hamsters of the superspecies Phodopus
sungorus and heteromorphism of the sex chromosomes in the females.
Doklady Akademii Nauk, SSSR, Biological Science Section 173:55-58.
Wynne-Edwards KE and Lisk RD (1984). Djungarian hamsters fail to conceive
in the presence of multiple males. Animal Behavior 32:626-628.
Wynne-Edwards KE and Lisk RD (1987). Behavioral interactions differentiate
Djungarian (Phodopus campbelli) and Siberian (Phodopus sungorus)
hamsters. Can. J. Zool. 65: 2229-2235.
Yudin BS, Galinka LI and Potapkina (1979). Mammals of the Altai-Sayanskoi
Gornoi Distrikt. Nauka, Novosibirsk, 296 pp. (in Russian).
... The Djungarian hamster is a species belonging to the Rodentia order and Cricetidae family (in the superfamily Muroidea). It is native to Siberia as well as semi-deserts in Kazakhstan (Steinlechner 1998). It is often used in laboratory investigations to study the influence of the photoperiod length on living organisms, as the colour of this species' coat changes in response to the length of the day (Hoffman 1978). ...
... In winter it becomes almost completely white, with a grey stripe. This trait is a determinant distinguishing the Djungarian hamster from the Campbell's dwarf hamster (Phodopus Campbelli), which is a species of similar size and colour, but it does not change its hair colour for winter (Steinlechner 1998). The Djungarian hamster is also frequently chosen as a companion animal. ...
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Mammals of the Altai-Sayanskoi Gornoi Distrikt
  • Bs Yudin
  • Li Galinka
Yudin BS, Galinka LI and Potapkina (1979). Mammals of the Altai-Sayanskoi Gornoi Distrikt. Nauka, Novosibirsk, 296 pp. (in Russian).