''Samburupithecus'' is an extinct

primate Primates is an order (biology), order of mammals, which is further divided into the Strepsirrhini, strepsirrhines, which include lemurs, galagos, and Lorisidae, lorisids; and the Haplorhini, haplorhines, which include Tarsiiformes, tarsiers a ...

that lived in

Kenya Kenya, officially the Republic of Kenya, is a country located in East Africa. With an estimated population of more than 52.4 million as of mid-2024, Kenya is the 27th-most-populous country in the world and the 7th most populous in Africa. ...

during the middle to late

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

. The one species in this genus, ''Samburupithecus kiptalami'', is known only from a

maxilla In vertebrates, the maxilla (: maxillae ) is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxil ...

fragment dated to 9.5 million years ago discovered in 1982 and formally described by . The type specimen KNM-SH 8531 was discovered by the Joint Japan-Kenya Expedition at the SH22 fossil site in the Samburu District, a locality where several other researchers found no ape fossils. ''Samburupithecus'' lived during the so-called "African ape gap" , a period from which very few hominoid fossils have been found in

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

until relatively recently. This apparent gap, however, is now populated by a diversity of apes such as '' Nakalipithecus'', '' Chororapithecus abyssinicus'', '' Otavipithecus'', and '' Nacholapithecus''.

Characteristics

''Samburupithecus'' was approximately and was most likely a

frugivorous A frugivore ( ) is an animal that thrives mostly on raw fruits or succulent fruit-like produce of plants such as roots, shoots, nuts and seeds. Approximately 20% of mammalian herbivores eat fruit. Frugivores are highly dependent on the abundance ...

terrestrial Terrestrial refers to things related to land or the planet Earth, as opposed to extraterrestrial. Terrestrial may also refer to: * Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on o ...

quadruped Quadrupedalism is a form of locomotion in which animals have four legs that are used to bear weight and move around. An animal or machine that usually maintains a four-legged posture and moves using all four legs is said to be a quadruped (fr ...

. Paleoenvironmental reconstructions indicate that ''Samburupithecus'' most likely lived in a wooded habitat surrounded by

savannah A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) biome and ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach th ...

. Defining cranial traits of this genus include low, broad zygomatics, straight

alveolar process The alveolar process () is the portion of bone containing the tooth sockets on the jaw bones (in humans, the maxilla and the mandible). The alveolar process is covered by gums within the mouth, terminating roughly along the line of the mandibu ...

and large

maxillary sinus The pyramid-shaped maxillary sinus (or antrum of Nathaniel Highmore (surgeon), Highmore) is the largest of the paranasal sinuses, located in the maxilla. It drains into the middle meatus of the noseHuman Anatomy, Jacobs, Elsevier, 2008, page 209- ...

. Defining dental traits include three-rooted

premolar The premolars, also called premolar Tooth (human), teeth, or bicuspids, are transitional teeth located between the Canine tooth, canine and Molar (tooth), molar teeth. In humans, there are two premolars per dental terminology#Quadrant, quadrant in ...

s, thick enamel and

bunodont The molars or molar teeth are large, flat teeth at the back of the mouth. They are more developed in mammals. They are used primarily to grind food during chewing. The name ''molar'' derives from Latin, ''molaris dens'', meaning "millstone tooth ...

cusps. The teeth in the ''Samburupithecus'' type maxilla are comparable in size to those of the type mandible of '' Nakalipithecus'', roughly the size of a modern female gorilla. The upper premolars of both are elongated mesiodistally (along the row of teeth), but those of ''Samburupithecus'' have more inflated cusps that are positioned more centrally, so that occlusal foveae and basins (depressions at top of teeth) are very restricted. This suggests that ''Samburupithecus'' was strongly specialized compared to other Miocene and extant apes. Another distinguishing feature between the two is the higher relief of the

dentine Dentin ( ) (American English) or dentine ( or ) (British English) () is a calcified tissue of the body and, along with enamel, cementum, and pulp, is one of the four major components of teeth. It is usually covered by enamel on the crown ...

/ enamel junction in ''Samburupithecus''. These elongated teeth are unlike many other Miocene hominoids, linking ''Samburupithecus'' the taxon to

gorilla Gorillas are primarily herbivorous, terrestrial great apes that inhabit the tropical forests of equatorial Africa. The genus ''Gorilla'' is divided into two species: the eastern gorilla and the western gorilla, and either four or five su ...

chimpanzee The chimpanzee (; ''Pan troglodytes''), also simply known as the chimp, is a species of Hominidae, great ape native to the forests and savannahs of tropical Africa. It has four confirmed subspecies and a fifth proposed one. When its close rel ...

s and

hominin The Hominini (hominins) form a taxonomic tribe of the subfamily Homininae (hominines). They comprise two extant genera: ''Homo'' (humans) and '' Pan'' (chimpanzees and bonobos), and in standard usage exclude the genus '' Gorilla'' ( gorillas) ...

s, but its relationships within this

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

is at present unclear. Because of this mixture of primitive and derived traits in the KNM-SH 8531 specimen, it has been proposed that ''Samburupithecus'' lived before the gorilla-chimpanzee-hominin split and, therefore, that it is a

common ancestor Common descent is a concept in evolutionary biology applicable when one species is the ancestor of two or more species later in time. According to modern evolutionary biology, all living beings could be descendants of a unique ancestor commonl ...

to these primates alongside '' Ouranopithecus''.

Notes

References

* * * * * * * * {{Taxonbar, from=Q28683 Miocene mammals of Africa Prehistoric apes Miocene primates of Africa Fauna of Kenya Fossil taxa described in 1997 Monotypic prehistoric primate genera

Characteristics

See also

Notes

References