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 were thought to be 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, as well as morphological measurements. Seven other extinct species of Giraffa are known from the fossil record.
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. 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.
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 and the okapi. 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.
The Cheyenne Mountain Zoo is a zoological park located southwest of downtown Colorado Springs, Colorado, on Cheyenne Mountain in the United States. At an elevation of 6,714 feet above sea level, it is the highest zoo in America. The zoo covers 140 acres, 40 of which are in use. The zoo houses more than 750 animals, representing nearly 150 different species, with more than 30 endangered species. The zoo was ranked the #4 best zoo in North America in 2018 by USA Today. It is accredited by the Association of Zoos and Aquariums.
The white rhinoceros, white rhino or square-lipped rhinoceros is the largest extant species of rhinoceros. It has a wide mouth used for grazing and is the most social of all rhino species. The white rhinoceros consists of two subspecies: the southern white rhinoceros, with an estimated 19,682–21,077 wild-living animals in the year 2015, and the much rarer northern white rhinoceros. The northern subspecies has very few remaining individuals, with only two confirmed left in 2018, both in captivity. Sudan, the world's last known male Northern white rhinoceros, died in Kenya on 19 March 2018 at age 45.
The gerenuk, also known as the giraffe gazelle, is a long-necked, medium-sized antelope found in parts of East Africa. The sole member of the genus Litocranius, the gerenuk was first described by the naturalist Victor Brooke in 1879. It is characterised by its long, slender neck and limbs. The antelope is 80–105 centimetres tall, and weighs between 18 and 52 kilograms. Two types of colouration are clearly visible on the smooth coat: the reddish brown back or the "saddle", and the lighter flanks, fawn to buff. The horns, present only on males, are lyre-shaped. Curving backward then slightly forward, these measure 25–44 cm.
The Masai giraffe, also spelled Maasai giraffe, and sometimes called the Kilimanjaro giraffe, is a species or subspecies of giraffe. It is native to East Africa. The Masai giraffe can be found in central and southern Kenya and in Tanzania. It has distinctive, irregular, jagged, star-like blotches that extend from the hooves to its head. The Masai giraffe is currently the national animal of Tanzania.
The northern giraffe, also known as three-horned giraffe, is the type species of giraffe, G. camelopardalis, and is native to North Africa, although alternative taxonomic hypotheses have proposed the northern giraffe as a separate species.
Kidepo Valley National Park is a 1,442 square kilometres (557 sq mi) national park in the Karamoja region in northeast Uganda. Kidepo is rugged savannah, dominated by the 2,750 metres (9,020 ft) Mount Morungole and transected by the Kidepo and Narus rivers.
Rothschild's giraffe is a subspecies of the Northern giraffe. It is one of the most endangered distinct populations of giraffe, with 1,399 mature individuals estimated in the wild in 2018.
Geographic isolation or other factors that prevent reproduction have resulted in a population of organisms with a change in genetic diversity and ultimately leads to the genetic isolation of species. Genetic isolates form new species through an evolutionary process known as speciation. Today, all the species diversity present on earth is the product of genetic isolate and evolution. The current distribution of genetic differences and isolation within and among populations is also influenced by genetic processes, which can give significant input into evolution's basic principles. The resulting genetic diversity within a species' distribution range is frequently unequally distributed, and large disparities can occur at the series of ranges when population dispersion and isolation are critical for species survival. The interrelationship of genetic drift, gene flow, and natural selection determines the level and dispersion of genetic differences between populations and among species assemblages. Geographic and natural elements may likewise add to these cycles and further impact species' advanced examples of hereditary variety such as genetic differences that cause genetic isolation. Genetic variations are often unequally distributed over a species' geographic distribution, with differences between populations at the geographic center and the range's extremities. In general, significant gene flow occurs in core populations, resulting in genetic uniformity, whereas low gene flow, severe genetic drift, and diverse selection conditions occur in range periphery populations, resulting in enhanced genetic isolation and heterogeneity among populations. Genetic differentiation resulted from genetic isolate occurs as significant alterations in genetic variations, such as fluctuations in allelic frequencies, that are accumulated in the populations over time with geographic regional boundaries. Significant genetic diversity can be detected towards the limits of a species' range, where population fragmentation and isolation are more likely to affect genetic processes. Fragmentation is the division of a large population into smaller, geographically separated habitats, resulting in genetic differences within and across groups is also the product of genetic isolate. Regional splitting is produced by a variety of factors, including environmental processes that regularly change a species' indigenous distribution. Additionally, human-caused environmental changes, such as deforestation, land degradation can result in fast changes in a species' distribution, resulting in population decrease, segmentation, and regional isolation. Consequently, communities became geographically and genetically isolated.
The Kordofan giraffe is a species or subspecies of giraffe found in northern Cameroon, southern Chad, the Central African Republic, and possibly western Sudan. Historically some confusion has existed over the exact range limit of this subspecies compared to the West African giraffe, with populations in e.g. northern Cameroon formerly assigned to the latter. Genetic work has also revealed that all "West African giraffe" in European zoos are in fact Kordofan giraffe. It has been suggested that the Nigerian giraffe's ancestor dispersed from East to North Africa during the Quaternary period and thereafter migrated to its current Sahel distribution in West Africa in response to the development of the Sahara desert. Compared to most other subspecies, the Kordofan giraffe is relatively small at 3.8 to 4.7 meters, with more irregular spots on the inner legs. Its English name is a reference to Kordofan in Sudan. There are around 2,300 individuals living in the wild.
The West African giraffe, also known as the Niger giraffe or Nigerian giraffe is a species or subspecies of the giraffe distinguished by its light colored spots. It is found in the Sahel of West Africa.
The South African giraffe or Cape giraffe is a species or subspecies of giraffe found in South Africa, Namibia, Botswana, Zimbabwe and Mozambique. It has rounded or blotched spots, some with star-like extensions on a light tan background, running down to the hooves.
Thornicroft's giraffe, also known as the Rhodesian giraffe or Luangwa giraffe, is a subspecies of giraffe. It is sometimes considered a species in its own right or a subspecies of the Masai giraffe. It is geographically isolated, occurring only in Zambia’s South Luangwa Valley. An estimated 550 live in the wild, with no captive populations. Its lifespan is 22 years for males and 28 years for females. The ecotype was originally named after Harry Scott Thornicroft, a commissioner in what was then North-Eastern Rhodesia and later Northern Rhodesia.
Sexual selection in mammals is a process the study of which started with Charles Darwin's observations concerning sexual selection, including sexual selection in humans, and in other mammals, consisting of male–male competition and mate choice that mold the development of future phenotypes in a population for a given species.
The Nubian giraffe, also known as Baringo giraffe or Ugandan giraffe is the nominate subspecies or species of giraffe. It is found in Ethiopia, Kenya, Uganda, South Sudan and Sudan. It is currently extinct in the wild of the Democratic Republic of Congo, Egypt and Eritrea. The Nubian giraffe used to be widespread in northeast Africa. The subspecies was listed as Critically Endangered by the IUCN in 2018 for the first time due to a 95% decline in the past three decades.
The Angolan giraffe, also known as the Namibian giraffe, is a species or subspecies of giraffe that is found in northern Namibia, south-western Zambia, Botswana, and western Zimbabwe.
The southern giraffe, also known as two-horned giraffe, is a species of giraffe native to Southern Africa. However, the IUCN currently recognizes only one species of giraffe with nine subspecies.
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