Leporidae

Leporidae is the family of rabbits and hares, containing over 70 species of extant mammals in all. The Latin word Leporidae means "those that resemble lepus" (hare). Together with the pikas, the Leporidae constitute the mammalian order Lagomorpha. Leporidae differ from pikas in that they have short, furry tails and elongated ears and hind legs.
The common name "rabbit" usually applies to all genera in the family except Lepus, while members of Lepus (almost half the species) usually are called hares. Like most common names, however, the distinction does not match current taxonomy completely; jackrabbits are members of Lepus, and members of the genera Pronolagus and Caprolagus sometimes are called hares.
Various countries across all continents except Antarctica and Australia have indigenous species of Leporidae. Furthermore, rabbits, most significantly the European rabbit, Oryctolagus cuniculus, also have been introduced to most of Oceania and to many other islands, where they pose serious ecological and commercial threats.
Characteristics
Leporids are small to moderately sized mammals, adapted for rapid movement. They have long hind legs, with four toes on each foot, and shorter fore legs, with five toes each. The soles of their feet are hairy, to improve grip while running, and they have strong claws on all of their toes. Leporids also have distinctive, elongated and mobile ears, and they have an excellent sense of hearing. Their eyes are large, and their night vision is good, reflecting their primarily nocturnal or crepuscular mode of living.
Leporids are all roughly the same shape and fall within a small range of sizes with short tails, ranging from the 21 cm (8 in) long Tres Marias cottontail to the 76 cm (30 in) long desert hare. Female leporids are almost always larger than males, which is unusual among terrestrial mammals, in which males are usually the larger sex.
Both rabbits and hares are almost exclusively herbivorous (although some Lepus species are known to eat carrion), feeding primarily on grasses and herbs, although they also eat leaves, fruit, and seeds of various kinds. They are coprophagous, as they pass food through their digestive systems twice, first expelling it as soft green feces, called cecotropes, which they then reingest, eventually producing hard, dark fecal pellets. Like rodents, they have powerful front incisor teeth, but they also have a smaller second pair of incisors to either side of the main teeth in the upper jaw, and the structure is different from that of rodent incisors. Also like rodents, leporids lack any canine teeth, but they do have more cheek teeth than rodents do. Their jaws also contain a large diastema. The dental formula of most, though not all, leporids is:
They have adapted to a remarkable range of habitats, from desert to tundra, forests, mountains, and swampland. Rabbits generally dig permanent burrows for shelter, the exact form of which varies between species. In contrast, hares rarely dig shelters of any kind, and their bodies are more suited to fast running than to burrowing.
The gestation period in leporids varies from around 28 to 50 days, and is generally longer in the hares. This is in part because young hares, or leverets, are born fully developed, with fur and open eyes, while rabbit kits are naked and blind at birth, having the security of the burrow to protect them. Leporids can have several litters a year, which can cause their population to expand dramatically in a short time when resources are plentiful.
Reproduction
Leporids are typically polygynandrous, and have highly developed social systems. Their social hierarchies determine which males mate when the females go into estrus, which happens throughout the year. Gestation periods are variable, but in general, higher latitudes correspond to shorter gestation periods. Moreover, the gestation time and litter size correspond to predation rates as well. Species nesting below ground tend to have lower predation rates and have larger litters.
Evolution
The oldest known leporid species date from the late Eocene, by which time the family was already present in both North America and Asia. Over the course of their evolution, this group has become increasingly adapted to lives of fast running and leaping. For example, Palaeolagus, an extinct rabbit from the Oligocene of North America, had shorter hind legs than modern forms (indicating it ran rather than hopped) though it was in most other respects quite rabbit-like. Two as yet unnamed fossil finds—dated ~48 Ma (from China) and ~53 Ma (India)—while primitive, display the characteristic leporid ankle, thus pushing the divergence of Ochotonidae and Leporidae yet further into the past.
The cladogram is from Matthee et al., 2004, based on nuclear and mitochondrial gene analysis.
Classification
Family Leporidae: rabbits and hares
Genus Pentalagus
Amami rabbit, Pentalagus furnessi
Genus Bunolagus
Riverine rabbit, Bunolagus monticularis
Genus Nesolagus
Sumatran striped rabbit, Nesolagus netscheri
Annamite striped rabbit, Nesolagus timminsi
Genus Romerolagus
Volcano rabbit, Romerolagus diazi
Genus Brachylagus
Pygmy rabbit, Brachylagus idahoensis
Genus Sylvilagus
Subgenus Tapeti
Swamp rabbit, Sylvilagus aquaticus
Andean tapetí, Sylvilagus andinus
Bogota tapetí, Sylvilagus apollinaris
Ecuadorian tapetí, Sylvilagus daulensis
Common tapetí, Sylvilagus brasiliensis
Fulvous tapetí, Sylvilagus fulvescens
Dice's cottontail, Sylvilagus dicei
Central American tapetí, Sylvilagus gabbi
Northern tapetí, Sylvilagus incitatus
Omilteme cottontail, Sylvilagus insonus
Nicefor's tapetí, Sylvilagus nicefori
Marsh rabbit, Sylvilagus palustris
Suriname tapetí, Sylvilagus parentum
Colombian tapetí, Sylvilagus salentus
Santa Marta tapetí, Sylvilagus sanctaemartae
Western tapetí, Sylvilagus surdaster
Coastal tapetí, Sylvilagus tapetillus
Venezuelan lowland rabbit, Sylvilagus varynaensis
Subgenus Sylvilagus
Desert cottontail, Sylvilagus audubonii
Mexican cottontail, Sylvilagus cunicularis
Eastern cottontail, Sylvilagus floridanus
Tres Marias cottontail, Sylvilagus graysoni
Robust cottontail, Sylvilagus holzneri
Mountain cottontail, Sylvilagus nuttallii
Appalachian cottontail, Sylvilagus obscurus
New England cottontail, Sylvilagus transitionalis
Subgenus Microlagus
Brush rabbit, Sylvilagus bachmani
Genus Oryctolagus
European rabbit, Oryctolagus cuniculus
Genus Poelagus
Bunyoro rabbit, Poelagus marjorita
Genus Pronolagus
Natal red rock hare, Pronolagus crassicaudatus
Jameson's red rock hare, Pronolagus randensis
Smith's red rock hare, Pronolagus rupestris
Hewitt's red rock hare, Pronolagus saundersiae
Genus Caprolagus
Hispid hare, Caprolagus hispidus
Genus Lepus
Subgenus Macrotolagus
Antelope jackrabbit, Lepus alleni
Subgenus Poecilolagus
Snowshoe hare, Lepus americanus
Subgenus Lepus
Arctic hare, Lepus arcticus
Alaskan hare, Lepus othus
Mountain hare, Lepus timidus
Subgenus Proeulagus
Black jackrabbit, Lepus insularis
Desert hare, Lepus tibetanus
Tolai hare, Lepus tolai
Subgenus Eulagos
Broom hare, Lepus castroviejoi
Yunnan hare, Lepus comus
Korean hare, Lepus coreanus
European hare, Lepus europaeus
Manchurian hare, Lepus mandshuricus
Ethiopian highland hare, Lepus starcki
Subgenus Sabanalagus
Ethiopian hare, Lepus fagani
African savanna hare, Lepus victoriae
Subgenus Indolagus
Hainan hare, Lepus hainanus
Indian hare, Lepus nigricollis
Burmese hare, Lepus peguensis
Subgenus Sinolagus
Chinese hare, Lepus sinensis
Subgenus Tarimolagus
Yarkand hare, Lepus yarkandensis
Incertae sedis
Tamaulipas jackrabbit, Lepus altamirae
Japanese hare, Lepus brachyurus
Black-tailed jackrabbit, Lepus californicus
White-sided jackrabbit, Lepus callotis
Cape hare, Lepus capensis
Corsican hare, Lepus corsicanus
Tehuantepec jackrabbit, Lepus flavigularis
Granada hare, Lepus granatensis
Abyssinian hare, Lepus habessinicus
Woolly hare, Lepus oiostolus
Scrub hare, Lepus saxatilis
White-tailed jackrabbit, Lepus townsendii
Genus †Serengetilagus
†Serengetilagus praecapensis
Genus †Aztlanolagus
†Aztlanolagus agilis
Predation
Predators of rabbits and hares include raccoons, snakes, eagles, canids, cats, mustelids, owls and hawks. Animals that eat roadkill rabbits include vultures and buzzards.
See also
Mara (mammal)
Viscacha
References
Leporidae
Mammal families
Extant Ypresian first appearances
Taxa named by Gotthelf Fischer von Waldheim