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39-509: Dinopithecus ("terrible ape") is an extinct genus of very large primates closely related to baboons , that lived during the Pliocene and Pleistocene epochs in South Africa and Ethiopia . It was named by British paleontologist Robert Broom in 1937 . The only species currently recognized is Dinopithecus ingens , as D. quadratirostris has been reassigned to the genus Soromandrillus. It

78-498: A baboon reinforcing its dominance. Baboon social dynamics can also vary; Robert Sapolsky reported on a troop, known as the Forest Troop, during the 1980s, which experienced significantly less aggressive social dynamics after its most aggressive males died off during a tuberculosis outbreak, leaving a skewed gender ratio of majority females and a minority of low-aggression males. This relatively low-aggression culture persisted into

117-420: A blunted point or cusp, which projects beyond the level of the other teeth. The root is single, but longer and thicker than that of the incisors, conical in form, compressed laterally, and marked by a slight groove on each side. The lingual surface also presents two depressions on either side of the surface separated by a ridge in between; these depressions are known as mesial and distal lingual fossae. In humans,

156-406: A confrontation occurs between different families or where a lower-ranking baboon takes the offensive, baboons show more interest in this exchange than those between members of the same family or when a higher-ranking baboon takes the offensive. This is because confrontations between different families or rank challenges can have a wider impact on the whole troop than an internal conflict in a family or

195-450: A facial aspect, maxillary canines are approximately one millimetre narrower than the central incisor. Their mesial aspects resemble the adjacent lateral incisors, while their distal aspects anticipate the first premolars. They are slightly darker and more yellow in color than the other anterior teeth. From a lingual aspect, they have well developed mesial and distal marginal ridges and a well-developed cingulum. A prominent lingual ridge divides

234-721: A separate evolutionary history. However, recent morphological and genetic studies of Papio show the hamadryas baboon to be more closely related to the northern baboon species (the Guinea and olive baboons) than to the southern species (the yellow and chacma baboons). In 2015 researchers found the oldest baboon fossil on record, dated at 2 million years old. All baboons have long, dog-like muzzles, heavy, powerful jaws with sharp canine teeth , close-set eyes, thick fur except on their muzzles, short tails, and rough spots on their protruding buttocks , called ischial callosities . These calluses are nerveless, hairless pads of skin that provide for

273-460: A six-month gestation, usually to one infant. The females tend to be the primary caretaker of the young, although several females may share the duties for all of their offspring. Offspring are weaned after about a year. They reach sexual maturity around five to eight years. Males leave their birth group, usually before they reach sexual maturity, whereas most females stay in the same group for their lives. Baboons in captivity live up to 45 years, while in

312-472: A strict dominance hierarchy based on the matriline . The hamadryas baboon group will typically include a younger male, but he will not attempt to mate with the females unless the older male is removed. In the harems of the hamadryas baboons, the males jealously guard their females, to the point of grabbing and biting the females when they wander too far away. Despite this, some males will raid harems for females. Such situations often cause aggressive fights between

351-579: A threat to young baboons. Large males will often confront them by flashing their eyelids, showing their teeth by yawning, making gestures, and chasing after the intruder/predator. Although they are not a prey species, baboons have been killed by the black mamba snake. This usually occurs when a baboon accidentally rouses the snake. The collective noun for baboons is "troop". Most baboons live in hierarchical troops. Group sizes are typically around 50 animals, but can vary between 5 and 250, depending on species, location and time of year. The structure within

390-431: A variety of plants and animals. Their principal predators are Nile crocodiles , leopards , lions and hyenas . Most baboons live in hierarchical troops containing harems . Baboons can determine from vocal exchanges what the dominance relations are between individuals. In general, each male can mate with any female; the mating order among the males depends partly on their social rank. Females typically give birth after

429-545: A very high percentage of fruit and relatively few leaves. No bones of the limbs or other parts beyond the skulls and teeth have been attributed to Dinopithecus , so it is impossible to know its mode of locomotion for certain. However, as a papionin of very large size, it most probably spent a significant amount of time on the ground and moved quadrupedally. Baboons Papio hamadryas Papio papio Papio anubis Papio cynocephalus Papio ursinus Papio kindae Baboons are primates comprising

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468-426: A weight of 77 kg (170 lb). The most distinguishing feature of the genus is its large size in comparison to other papionins . The only other papionin species to attain a similar size were Theropithecus brumpti and Theropithecus oswaldi . These, however, are very different from Dinopithecus in their dental morphology. Overall, the skull is similar to that of modern baboons, except that it generally lacks

507-519: Is high that those young are their offspring. Some females clearly prefer such friendly males as mates. However, males will also take infants during fights to protect themselves from harm. A female initiates mating by presenting her swollen rump to the male's face. In a wild baboon population of the Amboseli ecosystem in Kenya , inbreeding is avoided by mate choice . Inbreeding avoidance through mate choice

546-464: Is known from several infilled cave sites in South Africa , all of early Pleistocene age, including Skurweberg, Swartkrans (Member 1), and Sterkfontein (Member 4 or 5, but probably member 4). Dinopithecus ingens was approximately twice the size of the largest living baboons, with males averaging 46 kg (101 lb) and females 29 kg (64 lb), based on estimates from the molar teeth. In some cases males were estimated to reach in maturity

585-401: Is the nearly straight outline this tooth has compared to the maxillary canine which is slightly more bowed. As in the maxillary canine, the mesial incisal edge (or cusp ridge) is shorter than the distal side, however, the cusp is displaced slightly lingual relative to the cusp of the maxillary canine. Lingually, the surface of the tooth is much smoother compared to the very pronounced surface of

624-411: Is thought to only evolve when related possible sexual partners frequently encounter each other and there is a risk of inbreeding depression . Females typically give birth after a six-month gestation, usually to a single infant; twin baboons are rare and often do not survive. The young baboon weighs approximately 400 g and has a black epidermis when born. The females tend to be the primary caretaker of

663-505: The Kinda baboon has gained support for its species status after phylogenetic studies of all members of Papio . Many authors distinguish P. hamadryas as a full species, but regard all the others as subspecies of P. cynocephalus and refer to them collectively as "savanna baboons". This may not be helpful: it is based on the argument that the hamadryas baboon is behaviorally and physically distinct from other baboon species, and that this reflects

702-444: The carbon isotopes from samples of its tooth enamel found Dinopithecus to consume the smallest portion of grass and other savanna-based foods of any South African primate. Analysis of the microwear patterns on the molar teeth showed that they were similar to those of the living yellow baboon ( Papio cynocephalus ), suggesting a broad and eclectic diet. A study of the adaptations of the molar teeth suggested that D. ingens ate

741-522: The genus Papio , one of the 23 genera of Old World monkeys , in the family Cercopithecidae . There are six species of baboon: the hamadryas baboon , the Guinea baboon , the olive baboon , the yellow baboon , the Kinda baboon and the chacma baboon . Each species is native to one of six areas of Africa and the hamadryas baboon is also native to part of the Arabian Peninsula . Baboons are among

780-451: The 1990s and extended to new males coming into the troop, though Sapolsky observed that while unique, the troop was not an "unrecognizably different utopia"; there was still a dominance hierarchy and aggressive intrasexual competition amongst males. Furthermore, no new behaviours were created amongst the baboons, rather the difference was the frequency and context of existing baboon behaviour. Baboon mating behavior varies greatly depending on

819-462: The ages of seventeen and twenty-two months and shed between nine and twelve years. Transposition (positional interchange of two adjacent teeth) is a development defect that most commonly found in the permanent canine, with the maxillary being more commonly seen than mandibular. The upper canine frequently transposed with the first premolar whilst the lower canine transposed with the lateral incisor. Occasionally canines are congenitally missing. From

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858-457: The day and night. They often raid human dwellings, and in South Africa they break into homes and cars in search of food. Baboons will also raid farms, eating crops and preying on sheep, goats and poultry. Other than humans, the principal predators of baboons are leopards , lions , and spotted and striped hyenas . They are considered a difficult prey for the leopard, though, which is mostly

897-444: The disease to the primates upon close proximity. Pathogens have a high likelihood of spreading through humans and species of nonhuman primates, such as baboons. Canine teeth There are generally four canine teeth: two in the upper (maxillary) and two in the lower (mandibular) arch. A canine is placed laterally to (outside of) each lateral incisor and mesial to (inwards of) the premolars . They are larger and stronger than

936-447: The facial fossae (depressions on the sides of the muzzle and lower jaw) and maxillary ridges (ridges of bone that run along the upper sides of the snout). For these reasons, Dinopithecus is sometimes treated as a subgenus of Papio . Most living papionins are omnivorous feeders that consume a wide range of readily digestible plant parts, especially fruits, as well as insects and other invertebrates, and small vertebrates. An analysis of

975-410: The incisors, and their roots sink deeply into the bones, causing well-marked prominences upon the surface. They are the only teeth in dentition with a single cusp, their crowns are roughly triangular from a mesial viewpoint and trapezoidal from a buccal viewpoint . The crown is large and conical, very convex on its labial surface, a little hollowed and uneven on its lingual surface, and tapering to

1014-1025: The largest non- hominoid primates and have existed for at least two million years. Baboons vary in size and weight depending on the species. The smallest, the Kinda baboon , is 50 cm (20 in) in length and weighs only 14 kg (31 lb), while the largest, the chacma baboon , is up to 120 cm (47 in) in length and weighs 40 kg (88 lb). All baboons have long, dog-like muzzles, heavy, powerful jaws with sharp canine teeth , close-set eyes, thick fur except on their muzzles, short tails, and nerveless, hairless pads of skin on their protruding buttocks called ischial callosities that provide for sitting comfort. Male hamadryas baboons have large white manes. Baboons exhibit sexual dimorphism in size, colour and/or canine teeth development. Baboons are diurnal and terrestrial , but sleep in trees, or on high cliffs or rocks at night, away from predators. They are found in open savannas and woodlands across Africa. They are omnivorous and their diet consists of

1053-411: The lingual aspect in half and creates the mesial and distal lingual fossae between the lingual ridge and the marginal ridges. From a proximal aspect, they resemble the incisors, but are more robust, especially in the cingulum region. Incisally, they are visibly asymmetrical, as the mesial incisal edge is slightly shorter than the distal incisal edge, which places the cusp slightly mesial to the long axis of

1092-451: The males. Visual threats usually accompany these aggressive fights. These include a quick flashing of the eyelids accompanied by a yawn to show off the teeth. Some males succeed in taking a female from another's harem, called a "takeover". In several species, infant baboons are taken by the males as hostages, or used as shields during fights. Baboons can determine from vocal exchanges what the dominance relations are between individuals. When

1131-491: The maxillary canine, and the cingulum is noted as less developed. The cusp may be lost with attrition over time and may resemble an upper second permanent incisor. In many species the canine teeth in the upper or lower jaw, or in both jaws, are much larger in males than in females, where they are sometimes hidden or completely absent. Animals where this occurs include antelopes , musk-deer , camels , horses , wild boar , some apes, seals, narwhal , and walrus . Humans have

1170-402: The middle line than the upper, so that their summits correspond to the intervals between the upper canines and the lateral incisors. From a facial aspect, the mandibular canine is notably narrower mesiodistally than the maxillary one, the root is compressed mesiodistally with well-marked grooves on both sides and may be just as long as the maxillary (and at times bifurcated). A distinctive feature

1209-728: The proportionately smallest male canine teeth among all anthropoids and exhibit relatively little sexual dimorphism in canine tooth size. It has been proposed that the receding canine teeth in human males was likely to be a result of sexual selection for less aggressive partners by female humans. The dimorphism is also similarly less pronounced in chimpanzees . In non- synapsids , such as reptiles and crocodiles, teeth similar to canines may be termed "caniniform" ("canine-shaped") teeth. Teeth or appendages with similar appearances found in many snakes and invertebrates, such as spiders, are referred to as fangs , but are usually modified to inject venom. [REDACTED] This article incorporates text in

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1248-835: The sitting comfort of the baboon. All baboon species exhibit pronounced sexual dimorphism , usually in size, but also sometimes in colour. Males have much larger upper canines compared to females and use them in threat displays. Males of the hamadryas baboon species also have large white manes. Baboons are able to acquire orthographic processing skills , which form part of the ability to read. Baboons are terrestrial (ground dwelling) and are found in open savannah, open woodland and hills across Africa. They are omnivorous , highly opportunistic feeders and will eat virtually anything, including grasses, roots, seeds, leaves, bark, fruits, fungus, insects, spiders, worms, fish, shellfish , rodents, birds, vervet monkeys , and small antelopes . They are foragers and are active at irregular times throughout

1287-471: The social structure of the troop. In the mixed groups of savanna baboons, each male can mate with any female. The mating order among the males depends partially on their social ranking, and fights between males are not unusual. There are, however, more subtle possibilities; in mixed groups, males sometimes try to win the friendship of females. To garner this friendship, they may help groom the female, help care for her young, or supply her with food. The probability

1326-469: The tooth. They are also thicker labiolingually than mesiodistally. Because of the disproportionate incisal edges, the contacts are also asymmetrical. Mesially, the contact sits at the junction of the incisal and middle third of the crown, while distally, the contact as more cervical, in the middle of the middle third of the crown. The root of the maxillary canines are the longest root of any tooth and conical in shape. The lower canine teeth are placed nearer

1365-421: The troop varies considerably between hamadryas baboons and the remaining species, sometimes collectively referred to as savanna baboons. The hamadryas baboons often appear in very large groups composed of many smaller harems (one male with four or so females), to which females from elsewhere in the troop are recruited while they are still too young to breed. Other baboon species have a more promiscuous structure with

1404-517: The upper canine teeth (popularly called eye teeth, from their position under the eyes ) are larger and longer than the lower, and usually present a distinct basal ridge. Eruption typically occurs between the ages of eleven and twelve years for upper canines and between nine and ten years for lower canines. Upper deciduous canines also known as the baby tooth, typically erupt between the ages of sixteen and twenty-two months and shed between ten and twelve years. Lower deciduous canines typically erupt between

1443-527: The wild their life expectancy is between 20 and 30 years. In Egyptian mythology , Babi was the deification of the hamadryas baboon and was therefore a sacred animal. It was known as the attendant of Thoth , so is also called the sacred baboon. The 2009 documentary Baboon Woman examines the relationship between baboons and humans in South Africa. Herpesvirus papio family of viruses and strains infect baboons. Their effects on humans are unknown. Humans infected with Mycobacterium tuberculosis can transmit

1482-528: The wild they average between 20 and 30 years. Six species of Papio are recognized, although there is some disagreement about whether they are really full species or subspecies . [REDACTED] Unknown [REDACTED] [REDACTED] Unknown [REDACTED] [REDACTED] Unknown [REDACTED] [REDACTED] Unknown [REDACTED] [REDACTED] Unknown [REDACTED] [REDACTED] Unknown [REDACTED] Previously five species of baboon were recognised;

1521-421: The young, although several females will share the duties for all of their offspring. After about one year, the young animals are weaned. They reach sexual maturity in five to eight years. Baboon males leave their birth group, usually before they reach sexual maturity, whereas females are philopatric and stay in the same group their whole lives. Baboons in captivity have been known to live up to 45 years, while in

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