{{Short description|Species of mammal}} {{Redirect|Gerbil}} {{Redirect|Pet gerbil|other gerbil species|Gerbillinae}} {{Speciesbox | image = Meriones unguiculatus (wild).jpg | image_caption = Wild gerbil in Mongolia | status = LC | status_system = IUCN3.1 | status_ref = <ref>{{cite iucn |doi=10.2305/IUCN.UK.2016-3.RLTS.T13171A22432999.en |title=Meriones unguiculatus |last1=Batsaikhan |first1=N. |last2=Tsytsulina |first2=K |year=2016 }}</ref> | genus = Meriones | species = unguiculatus | authority = (Milne-Edwards, 1867){{r|Milne-Edwards}} }} [[File:Meriones unguiculatus - Wilhelma.jpg|thumb| Wilhelma Zoo, Stuttgart, Germany]] thumb|Pied cream gerbil in a curious pose The '''Mongolian gerbil''', also referred to as the '''Mongolian jird''' ('''''Meriones unguiculatus'''''), is a rodent belonging to the subfamily Gerbillinae.<ref name = MSW3>{{MSW3 Muroidea | id = 13001155 | page = 1239}}</ref> Their body size is typically {{cvt|110|–|135|mm|in|frac=4}}, with a {{cvt|95|–|120|mm|in|frac=4}} tail, and body weight {{cvt|60|–|130|g|oz|frac=4}}, with adult males larger than females.<ref>{{cite book |doi=10.1002/9781444318777.ch23 |chapter=The Laboratory Gerbil |title=The UFAW Handbook on the Care and Management of Laboratory and Other Research Animals |pages=327–347 |year=2010 |last1=Waiblinger |first1=Eva |isbn=978-1-4443-1877-7 }}</ref> The animal is used in science for research or kept as a small house pet. Their use in science dates back to the later half of the 19th century, but they only started to be kept as pets in the English-speaking world after 1954, when they were brought to the United States. However, their use in scientific research has fallen out of favor.
== Taxonomy and evolution == The first known mention of gerbils came in 1866, by Father Armand David, who sent "yellow rats" to the French National Museum of Natural History in Paris, from northern China. They were named ''Gerbillus unguiculatus'' by the scientist Alphonse Milne-Edwards in 1867.<ref name=Milne-Edwards>{{cite journal |last1=Milne-Edwards |first1=Alphonse |title=Observations sur quelques mammifères du nord de la Chine |journal=Annales des sciences naturelles. Zoologie et biologie animale |date=1867 |volume=7 |issue=5 |page=377 |url=https://www.biodiversitylibrary.org/item/92543#page/387/mode/1up |access-date=2021-03-16 |archive-date=2021-04-19 |archive-url=https://web.archive.org/web/20210419113047/https://www.biodiversitylibrary.org/item/92543#page/387/mode/1up |url-status=live }}</ref>
There is a popular misconception about the meaning of this scientific name, appearing both in printed works<ref>{{cite book|last=Engfer|first=Leeanne|title=My Pet Hamster and Gerbils|url=https://books.google.com/books?id=CMH4gAbK578C&pg=PA52|date=1997|publisher=Lerner Publications|isbn=978-0-8225-2261-4|pages=52–|access-date=2019-08-20|archive-date=2024-03-05|archive-url=https://web.archive.org/web/20240305191723/https://books.google.com/books?id=CMH4gAbK578C&pg=PA52#v=onepage&q&f=false|url-status=live}}</ref> and in websites,<ref>[https://www.theguardian.com/lifeandstyle/2003/jun/21/shopping.homes In from the cold] {{Webarchive|url=https://web.archive.org/web/20221205113323/https://www.theguardian.com/lifeandstyle/2003/jun/21/shopping.homes |date=2022-12-05 }}. ''The Guardian''. 21 June 2003</ref> due to the genus ''Meriones'' sharing the name with Greek warrior Meriones in Homer's ''Iliad''; however, translations like "clawed warrior" are incorrect. The genus was named by Johann Karl Wilhelm Illiger in 1811,<ref>[https://www.biodiversitylibrary.org/bibliography/106965#/summary Biodiversity Heritage Library] {{Webarchive|url=https://web.archive.org/web/20230926001317/https://www.biodiversitylibrary.org/bibliography/106965#/summary |date=2023-09-26 }} Prodromus systematis mammalium et avium additis terminis zoographicis utriusque classis, eorumque versione germanica, Illiger 1811 (PDF)</ref> deriving from the Greek word ''μηρος'' (femur). Combined with 'unguiculate', meaning to have claws or nails in Latin, the name can be loosely translated as 'clawed femur'.<ref>[http://www.egerbil.com/meriones-unguiculatus-clawed-warrior-gerbil-fact-or-fiction%3F The true meaning of Meriones unguiculatus: The Mongolian Gerbil] {{Webarchive|url=https://web.archive.org/web/20201202031407/http://egerbil.com/meriones-unguiculatus-clawed-warrior-gerbil-fact-or-fiction%3F |date=2020-12-02 }}. egerbil.com</ref>
==Habitat== Mongolian gerbils inhabit grassland, shrubland and desert, including semidesert and steppes in China, Mongolia, and the Russian Federation.<ref>{{Cite web|url=https://www.iucnredlist.org/en|title=The IUCN Red List of Threatened Species|website=IUCN Red List of Threatened Species|access-date=2019-04-09|archive-date=2020-03-04|archive-url=https://web.archive.org/web/20200304172225/https://www.iucnredlist.org/en|url-status=live}}</ref>
Soil on the steppes is sandy and is covered with grasses, herbs, and shrubs. The steppes have cool, dry winters and hot summers. The temperature can get up to {{convert|50|C|F}}, but the average temperature for most of the year is around {{convert|20|C|F}}.
In the wild, these gerbils live in patriarchal groups generally consisting of one parental pair, the most recent litter, and a few older pups; sometimes the dominant female's sister(s) also live with them. Only the dominant females will produce pups, and will mostly mate with the dominant male while in estrus (heat), female gerbils are generally more loyal than male gerbils.{{citation needed|date=September 2023}} One group of gerbils generally ranges over {{convert|325|-|1550|m2|sqyd|-2}}.<ref>{{cite journal |last1=A˚gren |first1=G. |last2=Zhou |first2=Q. |last3=Zhong |first3=W. |title=Ecology and social behaviour of Mongolian gerbils, Meriones unguiculatus, at Xilinhot, Inner Mongolia, China |journal=Animal Behaviour |date=January 1989 |volume=37 |pages=11–27 |doi=10.1016/0003-3472(89)90002-X |s2cid=53152632 }}</ref>
A group lives in a central burrow with 10–20 exits. Some deeper burrows with only one to three exits in their territory may exist. These deeper burrows are used to escape from predators when they are too far from the central burrow.
==In science== Gerbils have a long history of use in scientific research, although nowadays they are rarely used. For example, in the United Kingdom in 2017, only around 300 Mongolian gerbils were used in experimental procedures, compared to over 2 million mice.<ref>{{Cite web|url=https://www.gov.uk/government/statistics/statistics-of-scientific-procedures-on-living-animals-great-britain-2017|title=Statistics of scientific procedures on living animals, Great Britain 2017|website=GOV.UK|access-date=2019-04-09|archive-date=2019-04-09|archive-url=https://web.archive.org/web/20190409232441/https://www.gov.uk/government/statistics/statistics-of-scientific-procedures-on-living-animals-great-britain-2017|url-status=live}}</ref>
=== Tumblebrook Farm === Most gerbils used in scientific research are derived from the Tumblebrook Farm strain, which has its origins in 20 pairs of wild-caught Mongolian gerbils sent to Japan in 1935. Eleven of these animals were subsequently sent to Dr. V. Schwentker's Tumblebrook Farm in Brant Lake, New York, United States in 1954,<ref>{{cite journal |title=The Laboratory Rabbit, Guinea Pig, Hamster, and Other Rodents; Gerbils |last1=Batchelder |first1=Margaret |last2=Keller |first2=Lynn S. |last3=Ball Sauer |first3=Mary |last4=West |first4=Wanda L. |journal=The Laboratory Rabbit, Guinea Pig, Hamster, and Other Rodents |date=2011-12-16 |pages=1131–1155 |doi=10.1016/B978-0-12-380920-9.00052-3 |pmc=7158315 |quote=This foundation colony was established at Tumblebrook Farm at Brant Lake, NY, founded by Dr. Schwentker.}}</ref> with additional animals later sent to Charles River Ltd in Italy in 1996.<ref name=pmid29242387>{{cite journal |last1=Brekke |first1=Thomas D. |last2=Steele |first2=Katherine A. |last3=Mulley |first3=John F. |title=Inbred or Outbred? Genetic Diversity in Laboratory Rodent Colonies |journal=G3 |date=February 2018 |volume=8 |issue=2 |pages=679–686 |doi=10.1534/g3.117.300495 |pmc=5919727 |pmid=29242387 }}</ref><ref>{{cite journal |last1=Petrij |first1=F. |title=A Second Acromelanistic Allelomorph at the Albino Locus of the Mongolian Gerbil (''Meriones unguiculatus'') |journal=Journal of Heredity |date=1 January 2001 |volume=92 |issue=1 |pages=74–8 |pmid=11336233 |doi=10.1093/jhered/92.1.74 |doi-access=free }}</ref><ref>{{cite journal |last1=Stuermer |first1=Ingo W. |last2=Plotz |first2=Karsten |last3=Leybold |first3=Axel |last4=Zinke |first4=Olaf |last5=Kalberlah |first5=Otto |last6=Samjaa |first6=Ravchikh |last7=Scheich |first7=Henning |title=Intraspecific Allometric comparison of Laboratory gerbils with Mongolian Gerbils Trapped in the Wild Indicates Domestication in ''Meriones unguiculatus'' (Milne-Edwards, 1867) (Rodentia: Gerbillinae) |journal=Zoologischer Anzeiger |date=January 2003 |volume=242 |issue=3 |pages=249–266 |doi=10.1078/0044-5231-00102 |bibcode=2003ZooAn.242..249S }}</ref>
=== Hearing === Gerbils have a wide hearing range, from detection of low frequency foot drumming to higher frequency chirps and therefore may be a more suitable model of human hearing loss than mice and rats, which are high-frequency specialists.<ref>{{cite journal |last1=Abbas |first1=Leila |last2=Rivolta |first2=Marcelo N. |title=Aminoglycoside ototoxicity and hair cell ablation in the adult gerbil: A simple model to study hair cell loss and regeneration |journal=Hearing Research |date=July 2015 |volume=325 |pages=12–26 |doi=10.1016/j.heares.2015.03.002 |pmc=4441107 |pmid=25783988 }}</ref>
=== Vocal === Male gerbils can produce ultrasonic sounds with frequencies ranging from approximately 27 to 35 kHz and amplitudes ranging from approximately 0 to 70 dBa. Their larynx is involved in the production of these ultrasonic sounds. Experimentation revealed five findings of interest, which are that adults only emit ultrasonic sounds when stimulated socially, males signal more frequently than females, dominant males are more active in vocalizations than subordinate males, ultrasounds are triggered by conspecific odors, and that d-amphetamine, a central nervous system stimulant, contributes high levels of ultrasounds while chlorpromazine, an antipsychotic medication, lowers the emission rate.
=== Epilepsy === 10–20% of gerbils exhibit spontaneous epileptiform seizures, typically in response to a stressor such as handling or cage cleaning.<ref>{{cite journal |last1=Bertorelli |first1=R. |last2=Adami |first2=M. |last3=Ongini |first3=E. |title=The Mongolian gerbil in experimental epilepsy |journal=The Italian Journal of Neurological Sciences |date=March 1995 |volume=16 |issue=1–2 |pages=101–6 |pmid=7642342 |doi=10.1007/BF02229081 |s2cid=4551801 }}</ref> Epilepsy in gerbils has a genetic basis, and seizure-prone and seizure-resistant lines have been bred.<ref>{{cite book |doi=10.1016/b978-012088554-1/50023-2 |chapter=Inherited Epilepsy in Mongolian Gerbils |title=Models of Seizures and Epilepsy |pages=273–294 |year=2006 |last1=Buckmaster |first1=Paul S. |isbn=978-0-12-088554-1 }}</ref><ref>{{cite journal |last1=Fujisawa |first1=Nobuyoshi |last2=Maeda |first2=Yoshitaka |last3=Yamamoto |first3=Yoshitaka |last4=Sato |first4=Norimitsu L. |last5=Niimura |first5=Sueo |title=Newly Established Low Seizure Susceptible and Seizure-Prone Inbred Strains of Mongolian Gerbil. |journal=Experimental Animals |date=2003 |volume=52 |issue=2 |pages=169–72 |pmid=12806893 |doi=10.1538/expanim.52.169 |doi-access=free }}</ref>
=== Diabetes === Like other desert rodents such as fat sand rats, Mongolian gerbils are susceptible to diet-induced diabetes, although incidence is low.<ref>{{cite journal |last1=Boquist |first1=L. |title=Obesity and pancreatic islet hyperplasia in the Mongolian gerbil |journal=Diabetologia |date=August 1972 |volume=8 |issue=4 |pages=274–82 |pmid=4564648 |doi=10.1007/BF01225571 |doi-access=free }}</ref> A diabetes-prone line has recently been generated, showing that gerbil diabetes has at least some genetic basis.<ref>{{cite journal |last1=Li |first1=Xiaohong |last2=Lu |first2=Jing |last3=Wang |first3=Ying |last4=Huo |first4=Xueyun |last5=Li |first5=Zhenkun |last6=Zhang |first6=Shuangyue |last7=Li |first7=Changlong |last8=Guo |first8=Meng |last9=Du |first9=Xiaoyan |last10=Chen |first10=Zhenwen |last11=Bader |first11=Michael |title=Establishment and Characterization of a Newly Established Diabetic Gerbil Line |journal=PLOS ONE |date=18 July 2016 |volume=11 |issue=7 |article-number=e0159420 |doi=10.1371/journal.pone.0159420 |pmc=4948894 |pmid=27427908 |bibcode=2016PLoSO..1159420L |doi-access=free }}</ref><ref>{{cite journal |last1=Gong |first1=Jingjing |last2=Du |first2=Xiaoyan |last3=Li |first3=Zhenkun |last4=Li |first4=Xiaohong |last5=Guo |first5=Meng |last6=Lu |first6=Jing |last7=Wang |first7=Ying |last8=Chen |first8=Zhenwen |last9=Li |first9=Changlong |last10=Bader |first10=Michael |title=Differential expression of genes identified by suppression subtractive hybridization in liver and adipose tissue of gerbils with diabetes |journal=PLOS ONE |date=2 February 2018 |volume=13 |issue=2 |article-number=e0191212 |doi=10.1371/journal.pone.0191212 |pmc=5796689 |pmid=29394254 |bibcode=2018PLoSO..1391212G |doi-access=free }}</ref>
=== Genetics and genomics === Laboratory gerbils are derived from a small number of founders, and so genetic diversity was generally assumed to be low. Initial genetic studies based on small numbers of genetic markers appeared to support this,<ref>{{cite journal |last1=Neumann |first1=K |last2=Maak |first2=S |last3=Stuermer |first3=IW |last4=von Lengerken |first4=G |last5=Gattermann |first5=R |title=Low microsatellite variation in laboratory gerbrils. |journal=The Journal of Heredity |date=2001 |volume=92 |issue=1 |pages=71–4 |pmid=11336232 |doi=10.1093/jhered/92.1.71 |doi-access=free }}</ref><ref>{{cite journal |last1=Razzoli |first1=M |last2=Papa |first2=R |last3=Valsecchi |first3=P |last4=Nonnis Marzano |first4=F |title=AFLP to assess genetic variation in laboratory gerbils (''Meriones unguiculatus'') |journal=The Journal of Heredity |date=2003 |volume=94 |issue=6 |pages=507–11 |pmid=14691317 |doi=10.1093/jhered/esg097 |doi-access=free }}</ref> but more recent genome-wide Genotyping-by-Sequencing (GBS) data has shown that genetic diversity is actually quite high.<ref name=pmid29242387/> It has been suggested that laboratory gerbils should be considered domesticated, and designated "''M. unguiculatus'' forma domestica" to differentiate them from wild animals.<ref>{{cite journal |last1=Stuermer |first1=Ingo W. |last2=Plotz |first2=Karsten |last3=Leybold |first3=Axel |last4=Zinke |first4=Olaf |last5=Kalberlah |first5=Otto |last6=Samjaa |first6=Ravchikh |last7=Scheich |first7=Henning |title=Intraspecific Allometric comparison of Laboratory gerbils with Mongolian Gerbils Trapped in the Wild Indicates Domestication in ''Meriones unguiculatus'' (Milne-Edwards, 1867) (Rodentia: Gerbillinae) |journal=Zoologischer Anzeiger |date=January 2003 |volume=242 |issue=3 |pages=249–266 |doi=10.1078/0044-5231-00102 |bibcode=2003ZooAn.242..249S }}</ref> A Mongolian gerbil genome sequence was published in 2018<ref>{{cite journal |last1=Zorio |first1=Diego A.R. |last2=Monsma |first2=Scott |last3=Sanes |first3=Dan H. |last4=Golding |first4=Nace L. |last5=Rubel |first5=Edwin W. |last6=Wang |first6=Yuan |title=De novo sequencing and initial annotation of the Mongolian gerbil (''Meriones unguiculatus'') genome |journal=Genomics |volume=111 |issue=3 |pages=441–449 |date=March 2018 |doi=10.1016/j.ygeno.2018.03.001 |pmc=6129228 |pmid=29526484 }}</ref> and a genetic map comprising 22 linkage groups (one per chromosome) in 2019.<ref>{{cite journal |doi=10.1007/s00335-019-09799-z|biorxiv=10.1101/567016 |title=A high-density genetic map and molecular sex-typing assay for gerbils |year=2019 |last1=Brekke |first1=Thomas D. |last2=Supriya |first2=Sushmita |last3=Denver |first3=Megan G. |last4=Thom |first4=Angharad |last5=Steele |first5=Katherine A. |last6=Mulley |first6=John F. |journal=Mammalian Genome |volume=30 |issue=3–4 |pages=63–70 |pmid=30972478 |pmc=6491409 |doi-access=free }}</ref>
===Reproduction=== thumb|Mongolian gerbil young In the wild, Mongolian gerbils breed in February and October. Males do not become sexually mature for about 70–80 days, while the vaginal opening occurs in females about 33–50 days after birth.<ref name=":0">{{Cite journal|last1=Norris|first1=M. L.|last2=Adams|first2=C. E.|date=1979|title=Vaginal Opening in the Mongolian Gerbil, ''Meriones unguiculatus'': Normal Data and the Influence of Social Factors|journal=Laboratory Animals|volume=13|issue=2|pages=159–162|doi=10.1258/002367779780943459|pmid=480901|doi-access=free}}</ref> For other gerbils such as the hairy footed gerbil, sexual maturity has a slightly earlier and longer window of 60–90<ref>{{Cite journal|last1=Ascaray|first1=C.M.|last2=McLachlan|first2=A.|date=1991|title=Postnatal growth and development of the hairy-footed gerbil, ''Gerbillurus paebae exilis''|journal=South African Journal of Zoology|volume=26|issue=2|page=71|doi=10.1080/02541858.1991.11448234|doi-access=free}}</ref> days in comparison with a later and shorter window for Mongolian gerbils, 70–84 days.<ref name=":0" /> Females reach sexual maturity shortly after this opening occurs. They experience oestrus cycles every 4–6 days. Mongolian gerbils are regarded as monogamous within science. Even with this said, many Mongolian gerbils have still been found in laboratory tests regarding their sexual reproduction behavior to have shown signs of promiscuity and mating with other females while their monogamous partner is absent in laboratory setting.<ref name=":2">{{Cite journal|last1=Norris|first1=M. L.|last2=Adams|first2=C. E.|date=1972|journal=Reproduction|volume=31|issue=3|pages=447–450|doi=10.1530/jrf.0.0310447|pmid=4675127|title=Aggressive Behaviour and Reproduction in the Mongolian Gerbil, ''Meriones unguiculatus'', Relative to Age and Sexual Experience at Pairing|doi-access=free}}</ref>
Gerbils are for the most part selective when it comes to picking a mate for copulation. An average litter size for the Mongolian gerbil is around 4–8 pups. If the litter only contains around 1–2 young then the mother will neglect them and they will die from starvation. Mongolian gerbils are monogamous and mate with their selected partner for life. When their mate dies, many gerbils refrain from seeking other mates to reproduce with. Males generally find new mates whereas females may not. When older females lose their mate they almost always give up on seeking reproduction. Their behavior tends to vary when faced with different settings; in the wild, the large population of gerbils means that finding and selecting a mate is not a problem. Within a laboratory setting, though, many gerbils tend to keep to themselves and refrain from copulation.<ref name=":2"/>
==Behavior== Gerbils are social animals and live in groups in the wild.<ref>{{cite web|url=http://www.peteducation.com/article.cfm?c=2+2107+2254&aid=1622|title=PetCoach - Ask a Vet Online for Free, 24/7|access-date=3 June 2018|archive-date=3 March 2016|archive-url=https://web.archive.org/web/20160303173031/http://www.peteducation.com/article.cfm?c=2+2107+2254&aid=1622|url-status=live}}</ref> They rely on their sense of smell to identify other members of their clan.<ref>{{Cite web|title=Mongolian Gerbils - Split-caging|url=http://www.crittery.co.uk/index.php/geb-splitcage|access-date=2020-10-02|website=Crittery Exotics|language=en-gb|archive-date=2020-11-12|archive-url=https://web.archive.org/web/20201112022532/http://www.crittery.co.uk/index.php/geb-splitcage|url-status=live}}</ref> Gerbils are known to attack and often kill those carrying an unfamiliar scent. Groups of gerbils often have a "dominant" gerbil which may "bully" the others by humping them.<ref>{{cite web|url=http://egerbil.com/splittank.html|archive-url=https://web.archive.org/web/20140915142348/http://www.egerbil.com/splittank.html|title=Gerbil split-tanks by Elizabeth Arblaster|author=Elizabeth Arblaster|publisher=eGerbil|archive-date=15 September 2014|access-date=2 January 2015}}</ref>
== Diet == Gerbils naturally eat seeds of grasses, leaves, bulbs, and herbs. As pets, gerbils eat fruits such as pears, melons, apples, and oranges, and vegetables such as carrots, pumpkins, cucumbers, and fennels.<ref>{{Cite web |title=What To Feed Your Gerbils {{!}} RSPCA - RSPCA - rspca.org.uk |url=https://www.rspca.org.uk/adviceandwelfare/pets/rodents/gerbils/diet |access-date=2026-03-20 |website=RSPCA |language=en-US}}</ref>
== Relationship with humans == ===As pets=== {{anchor|Gerbils as pets|reason=Old, redundant, section name, may be linked.}}[[File:4rennmaeuse.jpg|right|thumb|Pet gerbils eating millet]] alt=A Mongolian Gerbil in captivity eating a toilet paper roll|thumb|Pet gerbil chewing toilet paper A gentle and hardy animal, the Mongolian gerbil has become a popular small house pet. It was first brought from China to Paris in the 19th century, and became a popular house pet there.<ref>{{cite web|url=http://www.huisdiereninfo.nl/content/gerbils.php|title=Gerbils|website=huisdiereninfo.nl|access-date=2012-01-26|archive-url=https://web.archive.org/web/20101221104630/http://www.huisdiereninfo.nl/content/gerbils.php|archive-date=2010-12-21}}</ref> It was later brought to the United States in 1954 by Dr. Victor Schwentker for use in research.<ref name="auto">{{cite journal | last1 = Schwentker | first1 = V | year = 1963 | title = The Gerbil. A new laboratory animal | journal = Ill Vet | volume = 6 | pages = 5–9 }}</ref> Dr. Schwentker soon recognized their potential as pet animals.<ref>{{cite journal |last1=Fisher |first1=Maryanna F. |last2=Llewellyn |first2=Gerald C. |title=The Mongolian Gerbil: Natural History, Care, and Maintenance |journal=The American Biology Teacher |date=1978 |volume=40 |issue=9 |pages=557–560 |doi=10.2307/4446413 |jstor=4446413 }}</ref> Selective breeding for the pet trade has resulted in a wide range of different color and pattern varieties.<ref>{{cite web|url=https://petearnest.com/breeding-gerbils/|title=Breeding Gerbils: Your Essential 10-Step Guide|work=PetEarnest.com|date=29 October 2023 |access-date=2023-10-29|archive-date=2023-10-29|archive-url=https://web.archive.org/web/20231029143057/https://petearnest.com/breeding-gerbils/|url-status=live}}</ref> Gerbils became popular pets in the US around the late 1950s and were imported to the United Kingdom in 1964, where they became popular pets too.<ref>{{cite book |doi=10.1016/B978-0-12-380920-9.00052-3 |chapter=Gerbils |title=The Laboratory Rabbit, Guinea Pig, Hamster, and Other Rodents |year=2012 |last1=Batchelder |first1=Margaret |last2=Keller |first2=Lynn S. |last3=Sauer |first3=Mary Ball |last4=l. West |first4=Wanda |pages=1131–1155 |pmc=7158315 |isbn=978-0-12-380920-9 |s2cid=215784531 }}</ref> They are now found in pet shops throughout the UK and the US.
However, due to the threat they pose to indigenous ecosystems and existing agricultural operations, it is illegal to purchase, import, or keep a gerbil as a pet in the U.S. state of California.<ref>See 14 Cal. Code Regs. § 671(c)(2)(J). The prohibition imposed by the California Fish and Game Commission also applies to all other members of order Rodentia, except for "domesticated races" of rats, mice, golden hamsters, guinea pigs, and chinchillas.</ref> It is also illegal to import the animal into New Zealand and Australia.<ref>{{cite web |title=Prohibited organisms in New Zealand |url=https://www.epa.govt.nz/industry-areas/new-organisms/prohibited-organisms-in-new-zealand/ |website=Environmental Protection Authority |access-date=5 January 2024 |archive-date=5 March 2024 |archive-url=https://web.archive.org/web/20240305191732/https://www.epa.govt.nz/industry-areas/new-organisms/prohibited-organisms-in-new-zealand/ |url-status=live }}</ref><ref>{{cite web |last1=Peters |first1=Andrew |last2=Hernandez-Jover |first2=Marta |title=It's illegal to have pet hamsters and gerbils in Australia. |url=https://www.abc.net.au/news/2022-12-29/the-risk-of-pet-hamsters-and-gerbils-in-australia/101812034 |website=ABC News Australia |date=28 December 2022 |access-date=5 January 2024 |archive-date=2024-01-05 |archive-url=https://web.archive.org/web/20240105212908/https://www.abc.net.au/news/2022-12-29/the-risk-of-pet-hamsters-and-gerbils-in-australia/101812034 |url-status=live }}</ref>
thumb|Gerbils enjoy human company. Gerbils are typically not aggressive, and they rarely bite unprovoked or without stress. They are small and easy to handle, since they are sociable creatures that enjoy the company of humans and other gerbils.<ref name="GIP-behaviour">''[http://www.gerbil-info.com/html/behave1.htm Behaviour] {{Webarchive|url=https://web.archive.org/web/20061215183115/http://www.gerbil-info.com/html/behave1.htm |date=2006-12-15 }}''. The Gerbil Information Page. Ed. Karin van Veen. Nov. 2001. Dutch Gerbil Study Group. Gerbil Genetics Group.</ref><ref name="AGS-handbook">''[http://agsgerbils.org/Gerbil_Care_Handbook/index.html Gerbil Care Handbook]''; {{Webarchive|url=https://web.archive.org/web/20070118084607/http://www.agsgerbils.org/Gerbil_Care_Handbook/index.html |date=2007-01-18 }}. The American Gerbil Society.</ref> Gerbils also have adapted their kidneys to produce a minimum of waste to conserve body fluids, which makes them very clean with little odor. Gerbils have many different aesthetic coat patterns, such as pied slate, described below.
===Health concerns===
Misalignment of incisors due to injury or malnutrition may result in overgrowth, which can cause injury to the roof of the mouth. Symptoms include a dropped or loss of appetite, drooling, weight loss, or foul breath.<ref name="caring">{{cite web|url=http://www.caringtogether.com/exotics/hamsters3.html#a|title=Animal Health Center Vets in Valdosta, GA|website=Animal Health Center Vets in Valdosta, GA|access-date=3 June 2018|archive-date=6 February 2017|archive-url=https://web.archive.org/web/20170206164257/http://www.caringtogether.com/exotics/hamsters3.html#a|url-status=live}}</ref>
Common injuries are caused by gerbils being dropped or falling, often while inside of a hamster ball, which can cause broken limbs or a fractured spine (for which there is no treatment).<ref name="caring"/><ref name="nanc">{{cite web|url=http://members.nanc.com/~mhaines/gerbil.html#Medical|title=Gerbil FAQ<!-- Bot generated title -->|access-date=3 June 2018|archive-url=https://web.archive.org/web/20120205134341/http://members.nanc.com/~mhaines/gerbil.html#Medical|archive-date=5 February 2012}}</ref>
A common problem for all small rodents is neglect, which can cause the gerbils to not receive adequate food and water, causing serious health concerns, including dehydration, starvation, stomach ulcers, eating of bedding material, and cannibalism.<ref name="caring"/>
Between 20 and 50% of pet gerbils have the seizure disorder epilepsy.<ref>{{cite web|url=http://www.petplace.com/small-mammals/gerbil-care/page4.aspx|title=Gerbil Care|date=13 July 2015|website=PetPlace|access-date=3 June 2018|archive-date=16 December 2014|archive-url=https://web.archive.org/web/20141216054138/http://www.petplace.com/small-mammals/gerbil-care/page4.aspx|url-status=live}}</ref> The seizures are thought to be caused by fright, handling, or a new environment. The attacks can be mild to severe, but do not typically appear to have any long-term effects, except for rare cases where death results from very severe seizures.<ref name="mi">{{cite web|url=http://www.michiganhumane.org/site/PageServer?pagename=vetcare_gerbils&printer_friendly=1|title=Michigan Humane Society: Veterinary Care<!-- Bot generated title -->|access-date=3 June 2018|archive-date=16 December 2014|archive-url=https://web.archive.org/web/20141216054539/http://www.michiganhumane.org/site/PageServer?pagename=vetcare_gerbils&printer_friendly=1|url-status=live}}</ref> A way to prevent a gerbil from having a seizure is to refrain from blowing in the animal's face (often used to "train" the pet not to bite). This technique is used in a lab environment to induce seizures for medical research.<ref>{{cite journal |last1=Bertorelli |first1=R. |last2=Adami |first2=M. |last3=Ongini |first3=E. |title=The Mongolian gerbil in experimental epilepsy |journal=The Italian Journal of Neurological Sciences |date=March 1995 |volume=16 |issue=1–2 |pages=101–106 |doi=10.1007/BF02229081 |pmid=7642342 |s2cid=4551801 }}</ref>
Tumors, both benign and malignant, are fairly common in pet gerbils, and are most common in females over the age of two. Usually, the tumors involve the ovaries, causing an extended abdomen, or the skin, with tumors most often developing around the ears, feet, mid-abdomen, and base of the tail, appearing as a lump or abscess.<ref name="mi"/>
Gerbils can lose their tails due to improper handling, being attacked by another animal, or getting their tails stuck. The first sign is a loss of fur from the tip of the tail, then, the skinless tail dies off and sloughs, with the stump usually healing without complications.<ref name="mi"/>
The most common infectious disease in gerbils is Tyzzer's disease, a bacterial disease, which stress can make animals more susceptible to. It produces symptoms such as ruffled fur, lethargy, hunched posture, poor appetite, diarrhoea, and often death. It quickly spreads between gerbils in close contact.<ref name="mi"/>
A problem with the inner ear may cause a gerbil to lean noticeably to one side. This may be caused by ear infections. Gerbils with "extreme white spotting" colouring are susceptible to deafness; this is thought to be due to the lack of pigmentation in and around the ear.<ref>{{cite web|url=http://www.egerbil.com/extremespot.html|archive-url=https://web.archive.org/web/20130708122350/http://www.egerbil.com/extremespot.html|title=Coat Colour Reference Guide|publisher=eGerbil|archive-date=8 July 2013|access-date=2 January 2015}}</ref><!-- Webpage is just a photo gallery, and a totally broken one at that. -->
===Captive-bred gerbils=== <!-- Image with unknown copyright status removed: thumb|right|A lilac gerbil --> thumb|right|A Burmese colored gerbil Many color varieties of gerbils are available in pet shops today, generally the result of years of selective breeding.
Over 20 different coat colors occur in the Mongolian gerbil, which has been captive-bred the longest.<ref>Anastasi, Donna. ''Gerbils: The Complete Guide to Gerbil Care''. Irvine: Bowtie Press, 2005.</ref>
The fat-tailed gerbil or duprasi is also kept as a pet. They are smaller than the common Mongolian gerbils, and have long, soft coats and short, fat tails, appearing more like a hamster. The variation on the normal duprasi coat is more gray in color, which may be a mutation, or it may be the result of hybrids between the Egyptian and Algerian subspecies of duprasi.<ref name="gerbilinfo">Ed. Karin van Veen. Nov. 2001. [http://www.gerbil-info.com/html/otherduprasiuk.htm "Fat-Tailed Gerbil (Duprasi)"]. {{Webarchive|url=https://web.archive.org/web/20141216064335/http://www.gerbil-info.com/html/otherduprasiuk.htm |date=2014-12-16 }}. ''The Gerbil Information Page''. Dutch Gerbil Study Group. Gerbil Genetics Group.</ref><ref>{{cite web|url=http://www.egerbil.com/duprasi.html|archive-url=https://web.archive.org/web/20130708123553/http://www.egerbil.com/duprasi.html|title=The Fat tail Gerbil ~ Pachyuromys Duprasis|author=Eddie Cope|publisher=eGerbil|archive-date=8 July 2013|access-date=2 January 2015}}</ref>
{{Main article|Fat-tailed gerbil}}
White spotting has been reported in not only the Mongolian gerbil, but also the pallid gerbil<ref>{{cite web|url=http://www.egerbil.com/pallid.html|archive-url=https://web.archive.org/web/20130708124325/http://www.egerbil.com/pallid.html|title=The Pallid Gerbil ~ Gerbillus perpallidus|author=Gill Colling|archive-date=8 July 2013|access-date=2 January 2015}}</ref> and possibly Sundervall's Jird.<ref>"Gerbil Genetics."''NGS Frontpage''. Ed. Julian Barker. 30 Nov. 2004. The National Gerbil Society.<http://www.gerbils.pwp.blueyonder.co.uk/gerbils/genetics.htm#Mutations {{Webarchive|url=https://web.archive.org/web/20061209012033/http://www.gerbils.pwp.blueyonder.co.uk/gerbils/genetics.htm#Mutations |date=2006-12-09 }}></ref>
A long-haired mutation, a grey agouti or chinchilla mutation, white spotting, and possibly a dilute mutation have also appeared in Shaw's jirds,<ref>{{cite web|url=http://www.egerbil.com/shawsjird.html|archive-url=https://web.archive.org/web/20130708122955/http://www.egerbil.com/shawsjird.html|title=Shaw's Jird (Meriones shawi)|publisher=eGerbil|archive-date=8 July 2013|access-date=2 January 2015}}</ref> and white spotting and a dilute mutation have shown up in bushy-tailed jirds.<ref>{{cite web|url=http://www.egerbil.com/bushy.html|archive-url=https://web.archive.org/web/20130708123529/http://www.egerbil.com/bushy.html|title=The Bushy Tail Jird ~ Sekeetamys calurus|publisher=eGerbil|archive-date=8 July 2013|access-date=2 January 2015}}</ref>
==References== {{Reflist}}
==External links== {{Commons category|Meriones unguiculatus}} * [http://www.gerbils.co.uk/ The National Gerbil Society] (U.K.) * [http://www.agsgerbils.org/ The American Gerbil Society] * [http://www.thegerbils.com/ The Gerbils.com – Everything about the gerbil] * [http://www.silveroakfarm.nl/Underwhite-dense.html The Underwhite/Underwhite Dense gene] * [https://web.archive.org/web/20140812144919/http://www.egerbil.com/ eGerbil - For everything gerbil!] * [https://gerbilcare.co.uk/ Gerbil Care]
{{Gerbillinae|G1.}} {{Taxonbar|from=Q649817}} {{Authority control}}
Category:Mammals described in 1867 Category:Meriones (rodent) Category:Rodents of Asia Category:Rodents as pets Category:Space-flown life Category:Taxa named by Alphonse Milne-Edwards