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Temporal range: 20–0  Ma
Early Miocene – recent
An okapi in Bristol Zoo, England
Giraffe Mikumi National Park.jpg
Masai giraffe (G. tippelskirchi) at the Mikumi National Park, Tanzania
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Superfamily: Giraffoidea
Family: Giraffidae
Gray, 1821
Type genus
Linnaeus, 1758

The Giraffidae are a family of ruminant artiodactyl mammals that share a common ancestor with deer and bovids. This family, once a diverse group spread throughout Eurasia and Africa, presently comprises only two extant genera, the giraffe (between one and eight, usually four, species of Giraffa , depending on taxonomic interpretation) and the okapi (the only known species of Okapia ). Both are confined to sub-Saharan Africa: the giraffe to the open savannas, and the okapi to the dense rainforest of the Congo. The two genera 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 ossicones.



ImageGenusLiving species
Okapia johnstoni1.jpg Okapia
Australia Zoo Giraffe-2 (17998331829).jpg Giraffa

Evolutionary background

Shansitherium and Palaeotragus microdon, two giraffids from the Miocene of Asia Shansitherium fuguensis.JPG
Shansitherium and Palaeotragus microdon, two giraffids from the Miocene of Asia

The giraffids are ruminants of the clade Pecora. Other extant pecorans are the families Antilocapridae (pronghorns), Cervidae (deer), Moschidae (musk deer), and Bovidae (cattle, goats and sheep, wildebeests and allies, and antelopes). The exact interrelationships among the pecorans have been debated, mainly focusing on the placement of Giraffidae, but a recent large-scale ruminant genome sequencing study suggests Antilocapridae are the sister taxon to Giraffidae, as shown in the cladogram below. [1]


The ancestors of pronghorn diverged from the giraffids in the Early Miocene. [1] This was in part of a relatively late mammal diversification following a climate change that transformed subtropical woodlands into open savannah grasslands.

The fossil record of giraffids and their stem-relatives is quite intensive, with fossil of these taxa include Gelocidae, Palaeomerycidae, Prolibytheridae, and Climacoceratidae. [2] [3] It is thought that the palaeomerycids, prolibytherids, climacoceratids and the giraffids all form a clade of pecorans known as Giraffomorpha. [2] [4] The relationship between the climacoceratids and giraffids is supported by the presence of a bilobed canine, [2] and have been postulated into two hypotheses. One is the climacoceratids were the ancestors of the sivatheres, as both groups were large, deer-like giraffoids with branching antler-like ossicones, while an extinct basal group of giraffoids, canthumerycines, evolved into the ancestors of Giraffidae. [3] Another more commonly supported hypothesis is climacoceratids were merely the sister clade to giraffids, with sivatheres being either basal giraffids [2] or descended from a lineage that also includes the okapi. [5] While the current range of giraffids today is in Africa, the fossil record of the group has shown this family was once widespread throughout of Eurasia. [2] [3] [5]

Below is the phylogenetic relationships of giraffomorphs after Solounias (2007), [2] Sánchez et al. (2015) [4] and Ríos et al. (2017): [5]


Skeletal illustration of Helladotherium, now extinct Helladotherium.jpg
Skeletal illustration of Helladotherium , now extinct
Skeletal mount of Palaeotragus on display at the Tianjin Natural History Museum. Palaeotragus-Tianjin Natural History Museum.jpg
Skeletal mount of Palaeotragus on display at the Tianjin Natural History Museum.
Skeletal mount of Shansitherium tafeli on display at the Beijing Museum of Natural History. Shansitherium-Beijing Museum of Natural History.jpg
Skeletal mount of Shansitherium tafeli on display at the Beijing Museum of Natural History.

Below is the total taxonomy of valid extant and fossil taxa (as well as junior synonyms which are listed in the brackets).

Family GiraffidaeJ.E.Gray, 1821


Two giraffes Giraffes Mikumi National Park.jpg
Two giraffes

The giraffe stands 5–6 m (16–20 ft) tall, with males taller than females. The giraffe and the okapi have characteristic long necks and long legs. Ossicones are present on males and females in the giraffe, but only on males in the okapi. [6]

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 incisors or upper canines, replacing them with a tough, horny pad. An especially long diastema is seen between the front and cheek teeth. The latter are selenodont, adapted for grinding up tough plant matter. [7] Like most other ruminants, the dental formula for giraffids is Giraffids have prehensile tongues (specially adapted for grasping). [8]

The extant giraffids, the forest-dwelling okapi and the savannah-living giraffe, have several features in common, including a pair of skin-covered horns, called ossicones, up to 15 cm (5.9 in) long (absent in female okapis); a long, black, prehensile tongue; lobed canine teeth; patterned coats acting as camouflage; and a back sloping towards the rear. The okapi's neck is long compared to most ruminants, but not nearly so long as the giraffe's. Male giraffes are the tallest of all mammals: their horns reach 5.5 m (18 ft) above the ground and their shoulder 3.3 m (11 ft), whereas the okapi has a shoulder height of 1.7 m (5 ft 7 in). [9]


The two extant genera are now confined to sub-Saharan Africa. The okapi is restricted to a small range in the northern rainforest of the Democratic Republic of Congo. Although the range of the giraffe is considerably larger, it once covered an area twice the present size – all parts of Africa that could offer an arid and dry landscape furnished with trees. [9]


The social structure and behavior is markedly different in okapis and giraffes, but although little is known of the okapi's behavior in the wild, a few things are known to be present in both species: [9]

Giraffes are sociable, whereas okapis live mainly solitary lives. Giraffes temporarily form herds of up to 20 individuals; these herds can be mixed or uniform groups of males and females, young and adults. Okapis are normally seen in mother-offspring pairs, although they occasionally gather around a prime food source. Giraffe are not territorial, but have ranges that can dramatically vary between 5 and 654 km2 (1.9 and 252.5 sq mi) – depending on food availability, whereas okapis have individual ranges about 2.5–5 km2 (0.97–1.93 sq mi) in size.


  1. A grade of giraffids.
  2. A paraphyletic grade of palaeotragines ancestral to Sivatheriinae.

Related Research Articles

<span class="mw-page-title-main">Giraffe</span> Tall African hoofed mammal

The giraffe is a large African hoofed mammal belonging to the genus Giraffa. It is the tallest living terrestrial animal and the largest ruminant on Earth. Traditionally, giraffes have been thought of as one species, Giraffa camelopardalis, with nine subspecies. Most recently, researchers proposed dividing them into up to eight extant species due to new research into their mitochondrial and nuclear DNA, and individual species can be distinguished by their fur coat patterns. Seven other extinct species of Giraffa are known from the fossil record.

<span class="mw-page-title-main">Okapi</span> Species of mammal

The okapi, also known as the forest giraffe, Congolese giraffe and zebra giraffe, is an artiodactyl mammal that is endemic to the northeast Democratic Republic of the Congo in central Africa. However, non-invasive genetic identification has suggested that a population has occurred south-west of the Congo River as well. It is the only species in the genus Okapia. Although the okapi has striped markings reminiscent of zebras, it is most closely related to the giraffe. The okapi and the giraffe are the only living members of the family Giraffidae.

<span class="mw-page-title-main">Artiodactyl</span> Order of mammals

Artiodactyls are placental mammals belonging to the order Artiodactyla. Typically, they are ungulates which bear weight equally on two of their five toes: the third and fourth, often in the form of a hoof. The other three toes are either present, absent, vestigial, or pointing posteriorly. By contrast, most perissodactyls bear weight on an odd number of the five toes. Another difference between the two is that many artiodactyls digest plant cellulose in one or more stomach chambers rather than in their intestine as perissodactyls do. The advent of molecular biology, along with new fossil discoveries, found that cetaceans fall within this taxonomic branch, being most closely related to hippopotamuses. Some modern taxonomists thus apply the name Cetartiodactyla to this group, while others opt to include cetaceans within the existing name of Artiodactyla. Some researchers use "even-toed ungulates" to exclude cetaceans and only include terrestrial artiodactyls, making the term paraphyletic in nature.

<span class="mw-page-title-main">Mammal classification</span> Taxonomy of mammals

Mammalia is a class of animal within the phylum Chordata. Mammal classification has been through several iterations since Carl Linnaeus initially defined the class. No classification system is universally accepted; McKenna & Bell (1997) and Wilson & Reader (2005) provide useful recent compendiums. Many earlier ideas from Linnaeus et al. have been completely abandoned by modern taxonomists, among these are the idea that bats are related to birds or that humans represent a group outside of other living things. Competing ideas about the relationships of mammal orders do persist and are currently in development. Most significantly in recent years, cladistic thinking has led to an effort to ensure that all taxonomic designations represent monophyletic groups. The field has also seen a recent surge in interest and modification due to the results of molecular phylogenetics.

<span class="mw-page-title-main">Pecora</span> Infraorder of mammals

Pecora is an infraorder of even-toed hoofed mammals with ruminant digestion. Most members of Pecora have cranial appendages projecting from their frontal bones; only two extant genera lack them, Hydropotes and Moschus. The name "Pecora" comes from the Latin word pecus, which means "cattle". Although most pecorans have cranial appendages, only some of these are properly called "horns", and many scientists agree that these appendages did not arise from a common ancestor, but instead evolved independently on at least two occasions. Likewise, while Pecora as a group is supported by both molecular and morphological studies, morphological support for interrelationships between pecoran families is disputed.

<span class="mw-page-title-main">Ailuropodinae</span> Subfamily of bears

Ailuropodinae is a subfamily of Ursidae that contains only one extant species, the giant panda of China. The fossil record of this group has shown that various species of pandas were more widespread across the Holarctic, with species found in places such as Europe, much of Asia and even North America. The earliest pandas were not unlike other modern bear species in that they had an omnivorous diet but by around 2.4 million years ago, pandas have evolved to be more herbivorous.

<i>Sivatherium</i> Extinct genus of mammals

Sivatherium is an extinct genus of giraffid that ranged throughout Africa and Eurasia. The species Sivatherium giganteum is, by weight, one of the largest giraffids known, and also one of the largest ruminants of all time.

<span class="mw-page-title-main">Ossicone</span> Horn-like structure of giraffes, okapi, and extinct relatives

Ossicones are columnar or conical skin-covered bone structures on the heads of giraffes, male okapi, and some of their extinct relatives. Ossicones are distinguished from the superficially similar structures of horns and antlers by their unique development and a permanent covering of skin and fur.

<i>Giraffokeryx</i> Extinct genus of giraffe-like animals

Giraffokeryx is an extinct genus of medium-sized giraffids known from the Miocene of the Indian subcontinent and Eurasia. It is distinguished from other giraffids by the four ossicones on its head; one pair in front of the eyes on the anterior aspect of the frontal bone and the other behind the eyes in the frontoparietal region overhanging the temporal fossae. It has a brachydont dentition like in other giraffids and its legs and feet are of medium length. Giraffokeryx is considered monotypic by most authors, in the form of G. punjabiensis, but other species have been assigned to the genus:

<i>Bramatherium</i> Extinct genus of mammals

Bramatherium is an extinct genus of giraffids that ranged from India to Turkey in Asia. It is closely related to the larger Sivatherium.

<span class="mw-page-title-main">Palaeomerycidae</span> Extinct family of pecorans

The Palaeomerycidae is an extinct family of Neogene ruminants belonging to the infraorder Pecora. Palaeomerycids lived in Europe and Asia exclusively during the Miocene, coevolving with cervids, bovids, moschids, and tragulids there as part of a dramatic radiation of ruminants by the early Miocene.

Hydaspitherium is an extinct genus of giraffid artiodactyls that lived during the Cenozoic era during the Miocene epoch to the Pliocene epoch in Pakistan. Giraffids are represented in the late Miocene epoch of the Siwaliks by large Sivatheriinae such as Sivatherium, Bramatherium, Helladotherium, and Hydaspitherium. Hydaspitherium has been proposed to be synonymous with Bramatherium. H. megacephalum is restricted to the Dhok Pathan Formation in northern Pakistan.

<span class="mw-page-title-main">Giraffoidea</span> Superfamily of mammals

Giraffoidea is a superfamily that includes the families Climacoceratidae, Prolibytheriidae, and Giraffidae. The only extant members in the superfamily are the giraffes and okapi. The Climacoceratidae are also placed in the superfamily, but were originally placed within the family Palaeomerycidae.

This is a list of the taxonomic contributions of Major Percy Horace Gordon Powell-Cotton.

<span class="mw-page-title-main">Reticulated giraffe</span> Species of giraffe

The reticulated giraffe is a species/subspecies of giraffe native to the Horn of Africa. It is differentiated from other types of giraffe by its coat, which consists of large, polygonal, block-like spots, which extend onto the lower legs, tail and face. These prominent liver-red spots also show much less white between them, when compared to other giraffe species. While the reticulated giraffe may yet still be found in parts of its historic range, such as areas of Somalia and Ethiopia, its population stronghold is primarily within Kenya. There are approximately 8,500 individuals living in the wild.

<i>Enhydriodon</i> Extinct genus of carnivorans

Enhydriodon is an extinct genus of mustelids known from Africa, Pakistan and India that lived from the late Miocene to the early Pleistocene. It contains nine confirmed species, two debated species, and at least a few other undescribed species from Africa. The genus belongs to the tribe Enhydriodontini in the otter subfamily Lutrinae. Enhydriodon means "otter tooth" in Ancient Greek and is a reference to its dentition rather than to the Enhydra genus, which includes the modern sea otter and its two prehistoric relatives.

<span class="mw-page-title-main">Giraffomorpha</span> Clade of superfamilies of mammals

Giraffomorpha is a clade of pecoran ruminants containing the superfamilies Palaeomerycoidea (Palaeomerycidae) and Giraffoidea, of which the giraffe and okapi of the Giraffidae are the only extant members of the once-diverse clade as a result of a decline in diversity after the Miocene as a result of declines in temperatures. The clade is defined by the presence of ossicones, suggesting that the feature was developed as a result of basal, related evolutions between the two superfamilies rather than as an instance of parallel evolution. Giraffomorpha is also characterized by a lack of articular fossettes (hollows) in metatarsal bones III-IV.


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