Giraffidae
Encyclopedia
The giraffids are ruminant
artiodactyl mammals that share a common ancestor with deer
and bovid
s. The biological family
Giraffidae, once a diverse group spread throughout Eurasia
and Africa, contains only two living members, the giraffe
and the okapi
. Both are confined to sub-saharan Africa
: the giraffe to the open savanna
s, and the okapi to the dense rainforest
of the Congo
. The two species look very different on first sight, but share a number of common features, including a long, dark-coloured tongue, lobed canine teeth, and horns covered in skin, called "ossicone
s".
s or canines, replacing them with a tough, horny pad. There is an especially long diastema
between the front and cheek teeth. The latter are selenodont, adapted for grinding up tough plant matter.
Like most other ruminants, the dental formula
for giraffids is:
The behavior of the two living species shows little commonality, probably because of their different habitats and ecology.
Their closest fossil relatives include the deer-like palaeomerycid
s and the climacocerids
, many genera of the latter having once been identified as giraffes themselves.
Fossil records indicate that many other giraffids thrived between the Miocene
era (around 20 million years ago) and the recent past. One major group of extinct giraffids, the sivatheres, had enormous branching ossicones, and would have looked more like massive deer than giraffes.
Ruminant
A ruminant is a mammal of the order Artiodactyla that digests plant-based food by initially softening it within the animal's first compartment of the stomach, principally through bacterial actions, then regurgitating the semi-digested mass, now known as cud, and chewing it again...
artiodactyl mammals that share a common ancestor with deer
Deer
Deer are the ruminant mammals forming the family Cervidae. Species in the Cervidae family include white-tailed deer, elk, moose, red deer, reindeer, fallow deer, roe deer and chital. Male deer of all species and female reindeer grow and shed new antlers each year...
and bovid
Bovid
A bovid is any of almost 140 species of cloven-hoofed ruminant mammal at least the males of which bear characteristic unbranching horns covered in a permanent sheath of keratin....
s. The biological family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Giraffidae, once a diverse group spread throughout Eurasia
Eurasia
Eurasia is a continent or supercontinent comprising the traditional continents of Europe and Asia ; covering about 52,990,000 km2 or about 10.6% of the Earth's surface located primarily in the eastern and northern hemispheres...
and Africa, contains only two living members, the giraffe
Giraffe
The giraffe is an African even-toed ungulate mammal, the tallest of all extant land-living animal species, and the largest ruminant...
and the okapi
Okapi
The okapi , Okapia johnstoni, is a giraffid artiodactyl mammal native to the Ituri Rainforest, located in the northeast of the Democratic Republic of the Congo, in Central Africa...
. Both are confined to sub-saharan Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
: the giraffe to the open savanna
Savanna
A savanna, or savannah, is a grassland ecosystem characterized by the trees being sufficiently small or widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of C4 grasses.Some...
s, and the okapi to the dense rainforest
Rainforest
Rainforests are forests characterized by high rainfall, with definitions based on a minimum normal annual rainfall of 1750-2000 mm...
of the Congo
Democratic Republic of the Congo
The Democratic Republic of the Congo is a state located in Central Africa. It is the second largest country in Africa by area and the eleventh largest in the world...
. The two species look very different on first sight, but share a number of common features, including a long, dark-coloured tongue, lobed canine teeth, and horns covered in skin, called "ossicone
Ossicone
Ossicones are horn-like protuberances on the heads of giraffes, male okapis, and their extinct relatives, such as Sivatherium, and the climacoceratids, such as Climacoceras. Only giraffids have true ossicones...
s".
Features
Giraffids share many common features with other ruminants. They have cloven hooves and cannon bones, much like bovids, and a complex, four-chambered stomach. They have no upper incisorIncisor
Incisors are the first kind of tooth in heterodont mammals. They are located in the premaxilla above and mandible below.-Function:...
s or canines, replacing them with a tough, horny pad. There is an especially long diastema
Diastema (dentistry)
Diastema is a space or gap between two teeth. Many species of mammals have diastemata as a normal feature, most commonly between the incisors and molars.-In humans:...
between the front and cheek teeth. The latter are selenodont, adapted for grinding up tough plant matter.
Like most other ruminants, the dental formula
Dentition
Dentition pertains to the development of teeth and their arrangement in the mouth. In particular, the characteristic arrangement, kind, and number of teeth in a given species at a given age...
for giraffids is:
The behavior of the two living species shows little commonality, probably because of their different habitats and ecology.
Their closest fossil relatives include the deer-like palaeomerycid
Palaeomerycidae
Palaeomerycidae is an extinct family of ruminants , probably ancestral to deer and musk deer...
s and the climacocerids
Climacoceratidae
Climacoceratidae is a family of superficially deer-like artiodactyl ungulates that were restricted to the Miocene of Africa. They are close to the ancestry of giraffes, with some genera, such as Prolibytherium, having originally identified as being giraffes.The climacoceratids, namely, of what is...
, many genera of the latter having once been identified as giraffes themselves.
Fossil records indicate that many other giraffids thrived between the Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
era (around 20 million years ago) and the recent past. One major group of extinct giraffids, the sivatheres, had enormous branching ossicones, and would have looked more like massive deer than giraffes.
Classification
- ORDER ARTIODACTYLA
- Suborder RuminantiaRuminantiaRuminantia includes many of the well-known large grazing or browsing mammals: among them cattle, goats, sheep, deer, and antelope. All members of the Ruminantia are ruminants: they digest food in two steps, chewing and swallowing in the normal way to begin with, and then regurgitating the...
- Infraorder PecoraPecoraThe Pecora is a group of hoofed mammals that comprises most of the ruminants, including cattle, sheep, goats, antelopes,deer, giraffes, and pronghorn. The only extant members of the Ruminantia that are not pecorans are the chevrotains, which lack horns and whose four-chambered stomach is less...
- Superfamily GiraffoideaGiraffoideaGiraffoidea is a superfamily that includes the families of Climacoceratidae and Giraffidae. The only extant species in the superfamily are the giraffe and okapi...
- Family ClimacoceratidaeClimacoceratidaeClimacoceratidae is a family of superficially deer-like artiodactyl ungulates that were restricted to the Miocene of Africa. They are close to the ancestry of giraffes, with some genera, such as Prolibytherium, having originally identified as being giraffes.The climacoceratids, namely, of what is...
- †ClimacocerasClimacocerasClimacoceras was a genus of early Miocene artiodactyl ungulates of Africa and Europe. The members of Climacoceras were related to giraffes, as the genus was once placed within Giraffidae. Fossils of the two best known species of Climacoceras, C. africanus and C. gentryi have been both found in...
- †ProlibytheriumProlibytheriumProlibytherium is an extinct artiodactyl ungulate native to Early Miocene North Africa.The 1.80 m long creature was related to the modern giraffe and okapi. Unlike these, however, Prolibytherium had a set of large, leaf-shaped ossicones with a width of 35 cm...
- †Climacoceras
- Family Giraffidae
- †BirgerbohliniaBirgerbohliniaBirgerbohlinia is an extinct genus of giraffidae. It was first named by Crusafont Pairó and Villalta in 1951.-External links:* at the Paleobiology Database...
- †BohliniaBohliniaBohlinia is an extinct genus of the artiodactyl family Giraffidae. It was first named by the paleontologist Dr. W. Matthew in 1929, and contains two species, B. adoumi and B. attica. The species B. attica has been reclassified several times since its description being first named Camelopardalis...
- †BramatheriumBramatheriumBramatherium is an extinct genus of giraffe that ranged from India to Turkey in Asia. It is closely related to the larger Sivatherium.-Etymology:...
- †DecennatheriumDecennatheriumDecennatherium is an extinct genus of giraffidae. It was first named by Crusafont Pairo in 1952.-External links:* at the Paleobiology Database...
- GiraffaGiraffaGiraffa is a genus of mammals in the Giraffidae family. The genus consists of seven species including the giraffe, Giraffa camelopardalis, the only extant species.- Species :There are six species in the genus Giraffa....
including the GiraffeGiraffeThe giraffe is an African even-toed ungulate mammal, the tallest of all extant land-living animal species, and the largest ruminant...
, Giraffa camelopardalis - †GiraffokeryxGiraffokeryxGiraffokeryx was a primitive giraffid that lived in the Miocene age around 27 million years ago in Asia, Europe, and Africa. It had two pairs of elongated ossicones, one pair above its eyes, and the other pair upon the snout. Although it bore a very superficial resemblance to the modern Okapi, it...
- †HelladotheriumHelladotheriumHelladotherium is an extinct genus of Sivatherine Giraffid from Europe, Africa, and Asia during the Miocene. The most complete skeleton is that of a female, based on a comparison with an intact female Sivatherium giganteum skull.- Sources :...
- †HonanotheriumHonanotheriumHonanotherium schlosseri was a giraffid ancestral to the modern giraffe from the late Miocene of Hunan Province, China. It would have resembled a modern giraffe, but, somewhat shorter.-Etymology:...
- †MacedonitheriumMacedonitheriumMacedonitherium is an extinct genus of giraffidae. It was first named by Sickenberg in 1967.-External links:* at the Paleobiology Database...
- †MitilanotheriumMitilanotheriumMitilanotherium is an extinct genus of giraffe from the Pliocene and Pleistocene of Europe.It was a medium-sized giraffid, resembling the modern okapi, with two long ossicones directly above its eyes, and relatively long and slender limbs. Fossils have been found in Greece, Romania, Ukraine, and...
- Okapia including the OkapiOkapiThe okapi , Okapia johnstoni, is a giraffid artiodactyl mammal native to the Ituri Rainforest, located in the northeast of the Democratic Republic of the Congo, in Central Africa...
, Okapia johnstoni - †PalaeogiraffaPalaeogiraffaPalaeogiraffa is an extinct genus of giraffidae. It was first named by Bonis an Bouvrain in 2003, and contains one species, P. major.-External links:* at the Paleobiology Database...
- †Paleotragus
- †ProgiraffaProgiraffaProgiraffa is an extinct genus of giraffidae. It was first named by Pilgrim in 1908.-External links:* at the Paleobiology Database...
- †PropalaeomeryxPropalaeomeryxPropalaeomeryx is an extinct genus of giraffidae. It was first named by Lydekker in 1883.-External links:* at the Paleobiology Database...
- †SamotheriumSamotheriumSamotherium is an extinct genus of giraffe from the Miocene and Pliocene of Eurasia and Africa. Samotherium had two ossicones on its head, and long legs. The ossicones usually pointed upward, and were curved backwards, with males having larger, more curved ossicones, though, in the Chinese...
- †ShansitheriumShansitheriumShansitherium is an extinct genus of superficially moose- or antelope-like giraffe from the late Miocene epoch of Shanxi Province, China. They were closely related to the genus Samotherium....
- †SivatheriumSivatheriumSivatherium ' is an extinct genus of giraffid that ranged throughout Africa to Southern Asia . The African species, S...
- †Birgerbohlinia
- Family Climacoceratidae
- Superfamily Giraffoidea
- Infraorder Pecora
- Suborder Ruminantia