The Bovidae comprise the biological family of , ruminant that includes Bos, bison, Bubalina, (including Caprinae), Ovis and goats. A member of this family is called a bovid. With 143 Extant taxon species and 300 known Extinction, the family Bovidae consists of 11 (or two) major subfamilies and thirteen major tribes. The family evolved 20 million years ago, in the early Miocene.
The bovids show great variation in size and Fur colouration. Except some Polled livestock, all male bovids have two or more horns, and in many species, females possess horns, too. The size and shape of the horns vary greatly, but the basic structure is always one or more pairs of simple bony protrusions without branches, often having a spiral, twisted or fluted form, each covered in a permanent sheath of keratin. Most bovids bear 30 to 32 teeth.
Most bovids are diurnality. Social activity and feeding usually peak during dawn and dusk. Bovids typically rest before dawn, during midday, and after dark. They have various methods of social organisation and social behaviour, which are classified into solitary and gregarious behaviour. Bovids use different forms of vocal, olfactory, and tangible communication. Most species alternately feed and ruminate throughout the day. While small bovids forage in dense and closed habitat, larger species feed on high-fiber vegetation in open grasslands. Most bovids are polygynous. Mature bovids mate at least once a year and smaller species may even mate twice. In some species, neonate bovids remain hidden for a week to two months, regularly nursed by their mothers; in other species, neonates are followers, accompanying their dams, rather than tending to remain hidden.
The greatest diversities of bovids occur in Africa. The maximum concentration of species is in the of Eastern Africa. Other bovid species also occur in Europe, Asia, and North America. Bovidae includes a number of Domestication species, including three whose use has spread worldwide, namely cattle, sheep, and goats. Dairy products, such as milk, butter, and cheese, are manufactured largely from domestic cattle. Bovids are also raised for their leather, meat, and wool.
Until the beginning of the 21st century it was understood that the family Moschidae (musk deer) was sister taxon to Cervidae. However, a 2003 phylogenetic study by Alexandre Hassanin (of National Museum of Natural History, France) and colleagues, based on and nuclear analyses, revealed that Moschidae and Bovidae form a clade sister to Cervidae. According to the study, Cervidae diverged from the Bovidae-Moschidae clade 27 to 28 million years ago. The following cladogram is based on the 2003 study.
Molecular studies have supported monophyly in the family Bovidae (a group of organisms comprises an ancestral species and all their descendants). The number of subfamily in Bovidae is disputed, with suggestions of as many as ten and as few as two subfamilies. However, molecular, morphological and fossil evidence indicates the existence of eight distinct subfamilies: Aepycerotinae (consisting of just the impala), Alcelaphinae (bontebok, hartebeest, wildebeest and relatives), Antilopinae (several antelopes, gazelles, and relatives), Bovinae (cattle, buffaloes, bison and other antelopes), Caprinae (goats, sheep, ibex, serows and relatives), Cephalophinae (duikers), Hippotraginae (addax, oryx and relatives) and Reduncinae (reedbuck and kob antelopes). In addition, three extinct subfamilies are known: Hypsodontinae (mid-Miocene), Oiocerinae (Turolian) and the subfamily Tethytraginae, which contains Tethytragus (mid-Miocene).
In 1992, Alan W . Gentry of the Natural History Museum, London divided the eight major subfamilies of Bovidae into two major clades on the basis of their evolutionary history: the Boodontia, which comprised only the Bovinae, and the Aegodontia, which consisted of the rest of the subfamilies. Boodonts have somewhat primitive teeth, resembling those of oxen, whereas aegodonts have more advanced teeth like those of goats.
A controversy exists about the recognition of Peleinae and Pantholopinae, comprising the genera Grey rhebok and Pantholops respectively, as subfamily. In 2000, American biologist George Schaller and palaeontologist Elisabeth Vrba suggested the inclusion of Grey rhebok in Reduncinae,
Below is a cladogram based on Yang et al. , 2013 and Calamari, 2021:
Alternatively, all members of the Aegodontia can be classified within the subfamily Antilopinae, with the individual subfamilies being tribes in this treatment.
The present genera of Alcelaphinae appeared in the Pliocene. The extinct Alcelaphine genus Paramularius, which was the same in size as the hartebeest, is believed to have come into being in the Pliocene, but became extinct in the middle Pleistocene. Several genera of Hippotraginae are known since the Pliocene and Pleistocene. This subfamily appears to have diverged from the Alcelaphinae in the latter part of early Miocene. The Bovinae are believed to have diverged from the rest of the Bovidae in the early Miocene. The Boselaphini became extinct in Africa in the early Pliocene; their latest fossils were excavated in Langebaanweg (South Africa) and Lothagam (Kenya).
The bovids show great variation in size: the gaur can weigh more than , and stand high at the shoulder. The royal antelope, in sharp contrast, is only tall and weighs at most . The klipspringer, another small antelope, stands at the shoulder and weighs just .
Differences occur in pelage colouration, ranging from a pale white (as in the Arabian oryx) to black (as in the black wildebeest). However, only the intermediate shades, such as brown and reddish brown (as in the reedbuck), are commonly observed. In several species, females and juveniles exhibit a light-coloured coat, while those of males darken with age. As in the wildebeest, the coat may be marked with prominent or faint stripes. In some species such as the addax, the coat colour can vary by the season. and are often present.
Some species, such as the gemsbok, sable antelope, and Grant's gazelle, are with strongly disruptive facial markings that conceal the highly recognisable eye. Many species, such as gazelles, may be made to look flat, and hence to blend into the background, by countershading. The outlines of many bovids are broken up with bold disruptive colouration, the strongly contrasting patterns helping to delay recognition by predators. However, all the Hippotraginae (including the gemsbok) have pale bodies and faces with conspicuous markings. The zoologist Tim Caro describes this as difficult to explain, but given that the species are diurnal, he suggests that the markings may function in communication. Strongly contrasting leg colouration is common only in the Bovidae, where for example Bos, Ovis, bontebok and gemsbok have white stockings. Again, communication is the likely function.
Excepting some domesticated forms, all male bovids have horns, and in many species, females, too, possess horns. The size and shape of the horns vary greatly, but the basic structure is a pair of simple bony protrusions without branches, often having a spiral, twisted, or fluted form, each covered in a permanent sheath of keratin. Although horns occur in a single pair on almost all bovid species, there are exceptions such as the four-horned antelope and the Jacob sheep.
Male horn development has been linked to sexual selection, Horns are small spikes in the monogamous duikers and other small antelopes, whereas in the polygynous, they are large and elaborately formed (for example in a spiral structure, as in the giant eland). Thus, to some extent, horns depict the degree of competition among males in a species. However, the presence of horns in females is likely due to natural selection. The horns of females are usually smaller than those of males, and are sometimes of a different shape. The horns of female bovids are believed to have evolved for defence against predators or to express territoriality, as non-territorial females, which are able to use crypsis for predator defence, often do not have horns. Females possess horns only in half of the bovid genera, and females in these genera are heavier than those in the rest. Females use horns mainly for stabbing.
Excluding the cephalophines (duikers), tragelaphines (spiral-horned antelopes) and the Neotragini, most African bovids are gregarious and territorial. Males are forced to disperse on attaining sexual maturity, and must form their own territories, while females are not required to do so. Males that do not hold territories form bachelor herds. Competition takes place among males to acquire dominance, and fights tend to be more rigorous in limited . With the exception of migratory males, males generally hold the same territory throughout their lives. In the waterbuck, some male individuals, known as "satellite males", may be allowed into the territories of other males and have to wait till the owner grows old so they may acquire his territory. Lek mating, where males gather together and competitively display to potential mates, is known to exist among , , and . The tragelaphines, cattle, sheep, and goats are gregarious and not territorial. In these species, males must gain absolute dominance over all other males, and fights are not confined to territories. Males, therefore, spend years in body growth.
In the mating season, rutting males bellow to make their presence known to females. Muskoxen roar during male-male fights, and male saigas force air through their noses, producing a roar to deter rival males and attract females. Mothers also use vocal communication to locate their calves if they get separated. During fights over dominance, males tend to display themselves in an erect posture with a level muzzle.
Fighting techniques differ amongst the bovid families and also depend on their build. While the hartebeest fight on knees, others usually fight on all fours. Gazelles of various sizes use different methods of combat. Gazelles usually box, and in serious fights may clash and fence, consisting of hard blows from short range. Ibex, goat and sheep males stand upright and clash into each other downwards. Wildebeest use powerful head butting in aggressive clashes. If horns become entangled, the opponents move in a circular manner to unlock them. Muskoxen will ram into each other at high speeds. As a rule, only two bovids of equal build and level of defence engage in a fight, which is intended to determine the superior of the two. Individuals that are evidently inferior to others would rather flee than fight; for example, immature males do not fight with the mature bulls. Generally, bovids direct their attacks on the opponent's head rather than its body. The S-shaped horns, such as those on the impala, have various sections that help in ramming, holding, and stabbing. Serious fights leading to injury are rare.
All bovids mate at least once a year, and smaller species may even mate twice. Mating seasons occur typically during the rainy months for most bovids. As such, breeding might peak twice in the equatorial regions. The sheep and goats exhibit remarkable seasonality of reproduction, in the determination of which the annual cycle of daily photoperiod plays a pivotal role. Other factors that have a significant influence on this cycle include the temperature of the surroundings, nutritional status, social interactions, the date of parturition and the lactation period. A study of this phenomenon concluded that goats and sheep are short-day breeders. Mating in most sheep breeds begins in summer or early autumn. Mating in sheep is also affected by melatonin, that advances the onset of the breeding season; and thyroxine, that terminates the breeding season. Estrus lasts for at most a day in bovids, with the exception of bovines and tragelaphines. Except for the hartebeest and the topi, all bovids can detect estrus in females by testing the urine using the vomeronasal organ. Once the male is assured that the female is in estrus, he begins courtship displays; these displays vary greatly from the elaborate marches among gregarious species to the fervent licking of female genitalia among solitary species. Females, initially not receptive, ultimately mates with the male which has achieved dominance over others. Receptiveness is expressed by permission for mounting by the male and setting aside the tail by the female. Copulation generally takes a few seconds.
Gestational period varies among bovids - while duiker gestation ranges from 120 to 150 days, gestation in African buffalo ranges from 300 to 330 days. Usually, a single offspring is born (twins are less frequent), and it is able to stand and run by itself within an hour of birth. In monogamous species, males assist in defending their young, but that is not the case in polygynous species. Most newborn calves remain hidden for a week to two months, regularly nursed by their mothers. In some bovid species, the neonates start following about their mothers immediately or within a few days, as in the impala. Different bovids have different strategies for the defence of juveniles. For instance, while wildebeest mothers solely defend their young, buffaloes exhibit collective defence. Weaning might occur as early as two months (as in royal antelope) or as late as a year (as in muskox).
The earliest evidence of cattle domestication is from 8000 BC, suggesting that the process began in Cyprus and the Euphrates basin.
Bovid leather is tough and durable, with the additional advantage that it can be made into leathers of varying thicknesses - from soft clothing leather to hard shoe leather. While goat and cattle leather have a wide variety of use, sheepskin is suited only for clothing purposes.
Bone meal is an important fertilizer rich in calcium, phosphorus, and nitrogen, effective in removing soil acidity.
Evolutionary history
Early Miocene and before
Middle Miocene
Late Miocene
Plio-Pleistocene
Characteristics
Anatomy
Dentition
Ecology and behaviour
Activity
Diet
Sexuality and reproduction
Lifespan
Distribution
Interaction with humans
Domesticated animals
Animal products
In human culture
External links
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