Afropithecus

Last updated

Afropithecus
Temporal range: 18–16  Ma
O
S
D
C
P
T
J
K
Pg
N
Miocene
Afropithecus turkanensis 16-18 maf kenya.JPG
Skull cast
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Suborder: Haplorhini
Infraorder: Simiiformes
Superfamily: Hominoidea
Family: Afropithecidae
Genus: Afropithecus
Leakey & Leakey, 1986
Species:
A. turkanensis
Binomial name
Afropithecus turkanensis
Leakey & Leakey, 1986

Afropithecus is a genus of Miocene hominoid with the sole species Afropithecus turkanensis, it was excavated from a small site near Lake Turkana called Kalodirr in northern Kenya in 1986 and named by Richard Leakey and Meave Leakey. [1] The estimated age of Afropithecus is between 16 and 18 million years old, which was determined with radiometric dating techniques and the geological studies conducted by Broschetto and Brown from the University of Utah. [1] In total there are 46 recovered specimens from Kalodirr relating to Afropithecus consisting of cranial, mandible, dentition and post-cranial remains. The type specimen of Afropithecus turkanensis is KNM-WK 16999. [1]

Contents

Morphology

Richard Leakey and Meave Leakey first described Afropithecus turkanensis to be a large hominoid which appeared to have relatively thick enamel. [2] Leakey suggested that A. turkanensis shared postcranial features with the species Proconsul nyanzae , which is the best known Miocene genus with literally hundreds of fossils having been found representing almost all skeletal elements, and sharing cranial features with Aegyptopithecus zeuxis and Heliopithecus which had two weathered molars that indicated a general distinction from known large early catarrhines, and later concluded that A. turkanenensis was a primitive, arboreal quadruped similar to P. nyanzae, and that A. turkanensis had primitive facial morphology and derived dental characteristics that would suggest a diet of hard fruits. Leakey also synonymised Heliopithecus with Afropithecus. [3]

Cranial morphology

The type specimen, KNM-WT 16999 is composed of a long distinct snout, the facial skeleton, frontal, much of the coronal structure, most of the sphenoid, and relatively unworn adult dentition; the right orbit (virtually complete), the right zygomatic, the pterygoid, most of the sphenoid and lesser wings, the maxilla and premaxilla, and adult dentition with procumbent incisors. The surface on the right side maxilla and premaxilla along with the enamel on the right molars has been lost over time and has been replaced with calcite crystals, which only provide the general shape and not the details. [1]

From dentition it is known that the palate, which is almost completely calcified, of A. turkanensis is shallow, long and narrow with tooth rows that converge posteriorly, and it is probable the tooth rows were originally nearly parallel. A. turkanensis had a 6.5mm diastema between its very procumbent second incisor (KNM-WT 16999 had large, broad incisors) and the canine. [4]

The thickness of the enamel on the molars is often reported when fossils are being recorded and used to make comparisons across taxa. The thickness is referred to either as "thin" or "thick" and is commonly assessed as a linear measurement of the enamel on worn or naturally fractured teeth. From enamel testing it has been suggested that A. turkanensis is the oldest known thick-enamelled hominoid, which is what would distinguish it from Kenyapithecus . [4]

Post-cranial morphology

Post cranial remains such as KNM-WK 16901, includes an associated right fibula (lacking the proximal portion, and is approximately the same size as Pan troglodytes; 184 mm), a right proximal third metatarsal, a right fourth metatarsal lacking the head, and an incomplete first metatarsal head. [1]

Other post-cranial remains include: KNM-WK 17016P a large right ulna, and foot or hand bones: KNM-WK 17008, KNM-WK 18395. [1]

Feeding

Morphological analysis of the teeth and palate of Afropithecus suggests that it utilized a sclerocarpic foraging diet similar to members of Pitheciidae, in contrast to that of Morotopithecus . [5]

See also


Related Research Articles

<i>Kenyanthropus</i> Oldest-known tool-making hominin

Kenyanthropus is a hominin genus identified from the Lomekwi site by Lake Turkana, Kenya, dated to 3.3 to 3.2 million years ago during the Middle Pliocene. It contains one species, K. platyops, but may also include the 2 million year old Homo rudolfensis, or K. rudolfensis. Before its naming in 2001, Australopithecus afarensis was widely regarded as the only australopithecine to exist during the Middle Pliocene, but Kenyanthropus evinces a greater diversity than once acknowledged. Kenyanthropus is most recognisable by an unusually flat face and small teeth for such an early hominin, with values on the extremes or beyond the range of variation for australopithecines in regard to these features. Multiple australopithecine species may have coexisted by foraging for different food items, which may be reason why these apes anatomically differ in features related to chewing.

<i>Homo rudolfensis</i> Extinct hominin from the Early Pleistocene of East Africa

Homo rudolfensis is a species of archaic human from the Early Pleistocene of East Africa about 2 million years ago (mya). Because H. rudolfensis coexisted with several other hominins, it is debated what specimens can be confidently assigned to this species beyond the lectotype skull KNM-ER 1470 and other partial skull aspects. No bodily remains are definitively assigned to H. rudolfensis. Consequently, both its generic classification and validity are debated without any wide consensus, with some recommending the species to actually belong to the genus Australopithecus as A. rudolfensis or Kenyanthropus as K. rudolfensis, or that it is synonymous with the contemporaneous and anatomically similar H. habilis.

<i>Aegyptopithecus</i> Extinct single-species genus of primate

Aegyptopithecus is an early fossil catarrhine that predates the divergence between hominoids (apes) and cercopithecids. It is known from a single species, Aegyptopithecus zeuxis, which lived around 38-29.5 million years ago in the early part of the Oligocene epoch. It likely resembled modern-day New World monkeys, and was about the same size as a modern howler monkey, which is about 56 to 92 cm long. Aegyptopithecus fossils have been found in the Jebel Qatrani Formation of modern-day Egypt. Aegyptopithecus is believed to be a stem-catarrhine, a crucial link between Eocene and Miocene fossils.

<i>Australopithecus anamensis</i> Extinct hominin from Pliocene east Africa

Australopithecus anamensis is a hominin species that lived approximately between 4.2 and 3.8 million years ago and is the oldest known Australopithecus species, living during the Plio-Pleistocene era.

<i>Victoriapithecus</i> Extinct monkey from middle Miocene central Africa

Victoriapithecus macinnesi was a primate from the middle Miocene that lived approximately 15 to 17 million years ago in Northern and Eastern Africa. Through extensive field work on Maboko Island in Lake Victoria, Kenya, over 3,500 specimens have been found, making V. macinnesi one of the best-known fossil primates. It was previously thought that perhaps multiple species of Victoriapithecus were found, however the majority of fossils found indicate there is only one species, V. macinnesi. Victoriapithecus shows similarities to the extant subfamilies Colobinae and Cercopithecinae. However, Victoriapithecus predates the last common ancestor of these two groups and instead is thought to be a sister taxon.

<i>Ekembo nyanzae</i> Extinct species of mammal

Ekembo nyanzae, originally classed as a species of Proconsul, is a species of fossil primate first discovered by Louis Leakey on Rusinga Island in 1942, which he published in Nature in 1943. It is also known by the name Dryopithecus africanus. A joint publication of Wilfrid Le Gros Clark and Louis Leakey in 1951, "The Miocene Hominoidea of East Africa", first defines Proconsul nyanzae. In 1965 Simons and Pilbeam replaced Proconsul with Dryopithecus, using the same species names.

<i>Necrolemur</i> Extinct genus of primates

Necrolemur is a small bodied omomyid with body mass estimations ranging from 114 grams to 346 grams. Necrolemur’s teeth feature broad basins and blunt cusps, suggesting their diet consisted of mostly soft fruit, though examination of microwear patterns suggests that populations from lower latitudes also consumed insects and gums. While they do not sport a true tooth comb like modern lemurs, microwear patterns on their lower incisors suggest they engaged in fur grooming behaviors. Like tarsiers, Necrolemur had large, front-facing, close set eyes and were likely nocturnal. Analysis of cranial and postcranial fossils by paleontologists suggest members of the family Omomyidae, including the genus Necrolemur, possessed highly specialized adaptations for leaping.

Postcanine megadontia

Post-canine megadontia is a relative enlargement of the molars and premolars compared to the size of the incisors and canines. This phenomenon is seen in some early hominid ancestors such as Paranthropus aethiopicus.

<i>Nakalipithecus</i> Extinct species of ape from Miocene Kenya

Nakalipithecus nakayamai is an extinct species of great ape from Nakali, Kenya, from about 9.9–9.8 million years ago during the Late Miocene. It is known from a right jawbone with 3 molars and from 11 isolated teeth, and the specimen is presumed female as the teeth are similar in size to those of female gorillas and orangutans. Compared to other great apes, the canines are short, the enamel is thin, and the molars are flatter. Nakalipithecus is one of only three Late Miocene great apes known from Africa, the others being Samburupithecus and Chororapithecus. Nakalipithecus seems to have inhabited a sclerophyllous woodland environment.

<i>Lufengpithecus</i> Extinct genus of primates

Lufengpithecus is an extinct genus of ape in the subfamily Ponginae. It is known from thousands of dental remains and a few skulls and probably weighed about 50 kg (110 lb). It contains three species: L. lufengensis, L. hudienensis and L. keiyuanensis.

Enamel hypoplasia Medical condition

Enamel hypoplasia is a defect of the teeth in which the enamel is deficient in quantity, caused by defective enamel matrix formation during enamel development, as a result of inherited and acquired systemic condition(s). It can be identified as missing tooth structure and may manifest as pits or grooves in the crown of the affected teeth, and in extreme cases, some portions of the crown of the tooth may have no enamel, exposing the dentin. It may be generalized across the dentition or localized to a few teeth. Defects are categorized by shape or location. Common categories are pit-form, plane-form, linear-form, and localised enamel hypoplasia. Hypoplastic lesions are found in areas of the teeth where the enamel was being actively formed during a systemic or local disturbance. Since the formation of enamel extends over a long period of time, defects may be confined to one well-defined area of the affected teeth. Knowledge of chronological development of deciduous and permanent teeth makes it possible to determine the approximate time at which the developmental disturbance occurred. Enamel hypoplasia varies substantially among populations and can be used to infer health and behavioural impacts from the past. Defects have also been found in a variety of non-human animals.

Kamoyapithecus was a primate that lived in Africa during the late Oligocene period, about 24.2-27.5 million years ago. First found in 1948 as part of a University of California, Berkeley expedition, it was at first thought to be under a form of Proconsul by C.T. Madden in 1980, but after a re-examination by Meave Leakey and associates later, the fossils were moved under a new genus Kamoyapithecus, named after the renowned fossil finder Kamoya Kimeu. The genus is represented by only one species, K. hamiltoni.

<i>Morotopithecus</i> Species of extinct ape from Miocene central Africs

Morotopithecus is a species of fossil ape discovered in Miocene-age deposits of Moroto, Uganda.

Equatorius is an extinct genus of kenyapithecine primate found in central Kenya at the Tugen Hills. Thirty-eight large teeth belonging to this middle Miocene hominid in addition to a mandibular and partially complete skeleton dated 15.58 Ma and 15.36 Ma. were later found.

<i>Lufengpithecus lufengensis</i> Extinct species of mammal

Lufengpithecus lufengensis is a prehistoric species of hominoid from the Late Miocene found in China, named after the Lufeng site and dated around 6.2 Ma. It is the latest Miocene fossil ape that has been discovered in the entire world. Some researchers believe that genus Lufengpithecus could be an ancestor to African apes and hominids.

Plesiopithecus is an extinct genus of early strepsirrhine primate from the late Eocene.

Changes to the dental morphology and jaw are major elements of hominid evolution. These changes were driven by the types and processing of food eaten. The evolution of the jaw is thought to have facilitated encephalization, speech, and the formation of the uniquely human chin.

<i>Ekembo</i> Genus of mammals

Ekembo is an early ape (hominoid) genus found in 17- to 20-million-year-old sediments from the Miocene epoch. Specimens have been found at sites around the ancient Kisingiri volcano in Kenya on Rusinga Island and Mfangano Island in Lake Victoria. The name Ekembo is Suba for "ape" or "monkey".

<i>Epipliopithecus</i> Extinct genus of primates

Epipliopithecus vindobonensis is an extinct species of pliopithecoid primate recovered from the Middle Miocene deposits of Devínska Nová Ves fissure in western Slovakia. Epipliopithecus is one of the few pliopithecoids for which both cranial and post-cranial fossil material has been recovered. Most pliopithecoids are known only from fossilized teeth, whereas Epipliopithecus is known from three nearly complete skeletons. As such, Epipliopithecus has greatly informed the modern understanding of pliopithecoid anatomy, locomotion, and phylogeny.

<i>Otavipithecus</i> Extinct species of primate

Otavipithecus namibiensis is an extinct species of ape from the Miocene of Namibia. The fossils were discovered at the Berg Aukas mines in the foothills of the Otavi mountains, hence the generic name. The species was described in 1992 by Glenn Conroy and colleagues, and was at the time the only non-hominin fossil ape known from southern Africa. The fossils consist of part of the lower jawbone with molars, a partial frontal bone, a heavily damaged ulna, one vertebra and a partial finger bone.

References

  1. 1 2 3 4 5 6 Leakey RE, Leakey MG, Walker AC (July 1988). "Morphology of Afropithecus turkanensis from Kenya". Am. J. Phys. Anthropol. 76 (3): 289–307. doi:10.1002/ajpa.1330760303. PMID   3137824.
  2. Leakey MG; Leakey, R.E.; Richtsmeier, J.T.; Simons, E.L.; Walker, A.C. (1991). "Similarities in Aegyptopithecus and Afropithecus Facial Morphology". Folia Primatologica. 56 (2): 65–71. doi:10.1159/000156531. PMID   1904388.
  3. Smith TM, Martin LB, Leakey MG (March 2003). "Enamel thickness, microstructure and development in Afropithecus turkanensis". J. Hum. Evol. 44 (3): 283–306. CiteSeerX   10.1.1.494.8756 . doi:10.1016/S0047-2484(03)00006-X. PMID   12657518.
  4. 1 2 Kelley J, Smith TM (March 2003). "Age at first molar emergence in early Miocene Afropithecus turkanensis and life-history evolution in the Hominoidea". J. Hum. Evol. 44 (3): 307–29. doi:10.1016/S0047-2484(03)00005-8. PMID   12657519.
  5. Andrew S. Deane (2017). "Re-evaluating the diets of Morotopithecus bishopi and Afropithecus turkanensis: An anterior dentognathic perspective". Journal of Human Evolution. 112: 1–14. doi:10.1016/j.jhevol.2017.08.012. PMID   29037412.