| Cervus | |
|---|---|
 | |
| Cervus elaphus | |
Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Artiodactyla |
| Family: | Cervidae |
| Tribe: | Cervini |
| Genus: | Cervus Linnaeus,1758 |
| Type species | |
| Cervus elaphus | |
| Species | |
| |
Cervus is agenus ofdeer that primarily are native toEurasia, although one species occurs in northern Africa and another inNorth America. In addition to the species presently placed in this genus, it has included a whole range of other species now commonly placed in other genera. Additionally, the species-leveltaxonomy is in a state of flux.
Until the 1970s,Cervus also included the members of the generaAxis,Dama, andElaphurus, and until the late 1980s, it included members ofRucervus andRusa.[1]
In the third edition ofMammal Species of the World from 2005, only thered deer (C. elaphus) andsika deer (C. nippon) were recognized as species in the genusCervus.[1]Genetic andmorphological evidence suggest more species should be recognized.[2][3] For example, the speciesCervus canadensis (elk/wapiti) is considered a separate species.[4]
Within the red deerspecies group, some sources have recommended theCentral Asian red deer (Cervus hanglu) should be treated as a species.[2][4][5] If the Central Asian red deer (from theCaspian Sea to westernChina) is recognized as a species, it includes theYarkand deer andBactrian deer (the two may besynonymous), but it could possibly also include theKashmir stag, which has not been sampled in recent studies.[2][4] If it is included in the Central Asian red deer, the scientific name of that species isC. hanglu. If it is not included, the scientific name of that species isC. yarkandensis, and the Kashmir stag (C. hanglu) may represent a separatemonotypic species.[2][4] The Central Asian red deer was considered its own species (including the Yarkand deer, Kashmir stag and Bactrian deer as subspecies) by the IUCN in 2017,[6] and by theAmerican Society of Mammalogists in 2021.[7]
Others members of the red deer group, which may represent separate species, areC. corsicanus,C. wallichi andC. xanthopygus.[2][3] If so,C. corsicanus includes thesubspeciesC. c. barbarus (perhaps a synonym ofcorsicanus), and is restricted toMaghreb in North Africa,Corsica andSardinia.[2][4]C. wallichi would probably include the subspeciesC. w. kansuensis andC. w. macneilli (both are perhaps synonyms ofC. w. wallichi), and would be found fromTibet to central China.[2][4][8]C. xanthopygus would probably include the subspeciesC. x. alashanicus (perhaps a synonym ofC. x. xanthopygus), and would be found from theRussian Far East to northeastern China.[2][4][8] This would restrict the "true" red deer (C. elaphus) to Europe,Anatolia, theCaucasus and northwesternIran, and the elk/wapiti (C. canadensis) to North America and the Asian regions of theTian Shan,Altai, andGreat Khingan.[2] Alternatively, thebarbarus group species are subspecies of the "true" red deer, while theC. wallichii andC. xanthopygus groups are subspecies of the elk/wapiti.[4]
It has been proposed that thesika deer should be split into four species based on genetics, morphology and voice,[3] although this may be premature based on the presently available evidence.[9] If split, the potential species areC. yesoensis from northern and central Japan (Hokkaido and northern and centralHonshu),C. nippon of southern Japan (southern Honshu,Shikoku,Kyushu,Okinawa,Tsushima and other small islands),C. hortulorum of mainland Asia (theRussian Far East,Korea, central and easternChina and northernVietnam), andC. taiouanus ofTaiwan.[3]
A 2014mitochondrial DNA study showed the internal phylogeny ofCervus to be as follows:[10]
| Cervus |
| ||||||
The remains ofCervus are known from the early-mid Pliocene of China.[11]
Members of the genusCervus havepolygynous mating systems within harems.[12] Theseharems consist of several males, numerous females and their young offspring 1–3 years in age[13] Members of this genus have a yearly breeding season where they display sensory exploitation, intrasexual competition, and weaponry. Females will fight for optimal mating opportunities and sexually selection for males with larger antler size and/or greater roar quality.[14] The degree of polygyny and female aggregation is dependent on the level of food distribution. Females aggregating in areas with more food leading to larger harems[15] Female distribution influences the level of polygyny.
Female-female competition has been observed within harems in the red deer species (Cervus elaphus) prior to and during the mating season. Aggression is displayed through nose threats, kicking, and displacements. Elevated aggression has only been observed during thebreeding season. Competition can be for access to mates or reproductive resources such as food, or nesting areas.[14] Female-female aggression in ungulates is often overlooked because it is not as extravagant as male antler combat. Female conflicts occur so the winner has first access to the harem male at the start of the mating season before he is exhausted or low on sperm storage.[14]
While an emphasis in observations ofsexual selection is placed on combat using antlers, males with higher roaring rates are also being selected for. During the breeding season males will make calls to attract mates and compete with other males. Like antler size, mating call quality is an indicator of mate potential. Red deer can distinguish the calls of the males in their harem, others and their offspring.[16]
Females select for males with larger antlers which indirectly benefits them. Large antler size in males is a sign of health and strength. The visual display is a reliable indicator of mate quality, providing indirect benefits. The females are not directly affected by these characteristics, but they will produce more viable and fit offspring. Males with large antlers mate and sire more offspring than smaller, younger males. Large antler size is correlated with overall health, fitness and an increase in sperm production and quality.[12]
