Dormouse

Dormouse
A dormouse is a rodent of the family Gliridae (this family is also variously called Myoxidae or Muscardinidae by different taxonomists). Dormice are nocturnal animals found in Africa, Asia, and Europe. They are named for their long, dormant hibernation period of six months or longer.
The English name of the species derived from the French dormeuse, and the latter in turn possibly from the Languedocien radourmeire.
Etymology
The word dormouse comes from Middle English "dormous", of uncertain origin, possibly from a dialectal *dor-, from Old Norse "dár" (benumbed) + Middle English "mous" (mouse).
The word is sometimes conjectured to come from an Anglo-Norman derivative of dormir (to sleep), with the second element mistaken for mouse, but no such Anglo-Norman term is known to have existed.
The Latin name "glis", which is the origin of the scientific name, is from the Proto-Indo-European root *gl̥h₁éys ("weasel, mouse"), related to Sanskrit गिरि (girí, "mouse"), and Ancient Greek γαλέη (galéē, "weasel").
Characteristics
Dormice are small rodents, with body lengths between , and weight between . They are generally mouse-like in appearance, but with furred tails. They are largely arboreal, agile, and well adapted to climbing. Most species are nocturnal. Dormice have an excellent sense of hearing and signal each other with a variety of vocalisations.
Dormice are omnivorous, and typically feed on berries, flowers, fruits, insects, and nuts. They are unique among rodents in that they lack a cecum, a part of the gut used in other species to ferment vegetable matter. Their dental formula is similar to that of squirrels, although they often lack premolars:
Dormice breed once (or, occasionally, twice) each year, producing litters with an average of four young after a gestation period of 22–24 days. They can live for as long as five years. The young are born hairless and helpless, and their eyes do not open until about 18 days after birth. They typically become sexually mature after the end of their first hibernation. Dormice live in small family groups, with home ranges that vary widely between species and depend on the availability of food.
Hibernation
One of the most notable characteristics of those dormice that live in temperate zones is hibernation. They can hibernate six months out of the year, or even longer if the weather does not become warm enough, sometimes waking for brief periods to eat food they had previously stored nearby. During the summer, they accumulate fat in their bodies to nourish them through the hibernation period.
Relationship with humans
The edible dormouse (Glis glis) was considered a delicacy in ancient Rome, either as a savoury appetizer or as a dessert (dipped in honey and poppy seeds). The Romans used a special kind of enclosure, a glirarium, to raise and fatten dormice for the table. It is still considered a delicacy in Slovenia and in several places in Croatia, namely Lika, and the islands of Hvar and Brač. Dormouse fat was believed by the Elizabethans to induce sleep since the animal put on fat before hibernating.
In more recent years dormice have begun to enter the pet trade, though they are uncommon as pets and are considered an exotic pet. The woodland dormouse (Graphiurus murinus) is the most commonly seen species in the pet trade. Asian garden dormice (Eliomys melanurus) are also occasionally kept as pets.
Evolution
The Gliridae are one of the oldest extant rodent families, with a fossil record dating back to the early Eocene. As currently understood, they descended in Europe from early Paleogene ischyromyids such as Microparamys (Sparnacomys) chandoni. The early and middle Eocene genus Eogliravus represents the earliest and most primitive glirid taxon; the oldest species, Eogliravus wildi, is known from isolated teeth from the early Eocene of France and a complete specimen of the early middle Eocene of the Messel pit in Germany. They appear in Africa in the upper Miocene and only relatively recently in Asia. Many types of extinct dormouse species have been identified. During the Pleistocene, giant dormice the size of large rats, Leithia melitensis, lived on the islands of Malta and Sicily.
Classification
The family consists of 29 extant species, in three subfamilies and (arguably) nine genera:
Family Gliridae – Dormice
Subfamily Glirinae
Genus Glirulus
Japanese dormouse, Glirulus japonicus
Genus Glis
European edible dormouse, Glis glis
Iranian edible dormouse, Glis persicus
Subfamily Graphiurinae
Genus Graphiurus, African dormice
Angolan African dormouse, Graphiurus angolensis
Christy's dormouse, Graphiurus christyi
Walter Verheyen's African dormouse, Graphiurus walterverheyeni
Jentink's dormouse, Graphiurus crassicaudatus
Johnston's African dormouse, Graphiurus johnstoni
Kellen's dormouse, Graphiurus kelleni
Lorrain dormouse, Graphiurus lorraineus
Monard's dormouse, Graphiurus monardi
Nagtglas's African dormouse, Graphiurus nagtglasii
Rock dormouse, Graphiurus platyops
Silent dormouse, Graphiurus surdus
Small-eared dormouse, Graphiurus microtis
Spectacled dormouse, Graphiurus ocularis
Stone dormouse, Graphiurus rupicola
Woodland dormouse, Graphiurus murinus
Subfamily Leithiinae
Genus Chaetocauda
Chinese dormouse, Chaetocauda sichuanensis
Genus Dryomys
Balochistan forest dormouse, Dryomys niethammeri
Forest dormouse, Dryomys nitedula
Woolly dormouse, Dryomys laniger
Genus Eliomys, garden dormice
Asian garden dormouse, Eliomys melanurus
Garden dormouse, Eliomys quercinus
Maghreb garden dormouse, Eliomys munbyanus
Genus Hypnomys† (Balearic dormouse)
Majorcan giant dormouse, Hypnomys morphaeus†
Minorcan giant dormouse, Hypnomys mahonensis†
Genus Leithia†
Leithia cartei†
Maltese giant dormouse, Leithia melitensis†
Genus Muscardinus
Hazel dormouse, Muscardinus avellanarius
Genus Myomimus, mouse-tailed dormice
Masked mouse-tailed dormouse, Myomimus personatus
Roach's mouse-tailed dormouse, Myomimus roachi
Setzer's mouse-tailed dormouse, Myomimus setzeri
Genus Selevinia
Desert dormouse, Selevinia betpakdalaensis
Fossil species
Subfamily Bransatoglirinae
Genus Bransatoglis
Bransatoglis adroveri Majorca, Early Oligocene
Bransatoglis planus Eurasia, Early Oligocene
Genus Oligodyromys
References
Further reading
External links
Glirarium.org
Natural monuments of Japan
Extant Eocene first appearances