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Chalicotheriidae

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56-400: † Chalicotheriinae Gill, 1872 † Schizotheriinae Holland and Peterson, 1914 Chalicotheriidae (from Greek chalix , "gravel" and therion , "beast") is an extinct family of herbivorous , odd-toed ungulate (perissodactyl) mammals that lived in North America , Eurasia , and Africa from the Middle Eocene to the Early Pleistocene . They are often called chalicotheres ,

112-423: A bipedal position, such as the ground sloths , gorillas , and giant pandas . Chalicothere fossils are uncommon even in areas where other taxa of similar size are well-preserved, which suggests they were mostly solitary animals, and unlike horses, rhinos, and brontotheres, never evolved species that lived in herds. Only two species of chalicothere are known from complete skeletons, the schizotheriine Moropus from

168-425: A complex multilevel social structure. Reproductive units and male units are the two basic groupings. A band comprises a mix of multiple reproductive units and male units; a community is made up of one to four bands. Within the reproductive units the females are commonly closely related. Males will move from their natal group to try to control a unit of their own and females within the unit can choose to support or oppose

224-634: A complex, multilevel society similar to that of the hamadryas baboon . The smallest and most basic groups are the reproductive units, which include up to 12 females, their young, and one to four males, and the all-male units, which are made up of 2–15 males. The next level of gelada societies are the bands, which are made up of two to 27 reproductive units and several all-male units. Herds consist of up to 60 reproductive units that are sometimes from different bands and last for short times. Communities are made of one to four bands whose home ranges overlap extensively. A gelada typically lives around 15 years. Within

280-452: A conspicuous bright red patch of skin shaped like an hourglass on their chests. Females also have a bare patch of skin but it is less pronounced, except during estrus , when it brightens and exhibits a "necklace" of fluid-filled blisters. Males average 18.5 kg (41 lb) and females average 11 kg (24 lb) in weight. The head-body length is 50–75 cm (20–30 in) with a tail of 30–50 cm (12–20 in). The gelada has

336-636: A distinct preference for barley. In 2008, the IUCN assessed the gelada as least concern, although their population had reduced from an estimated 440,000 in the 1970s to around 200,000 in 2008. It is listed in Appendix II of CITES . Major threats to the gelada are a reduction of their range as a result of agricultural expansion and shooting as crop pests. Previously, these monkeys were trapped for use as laboratory animals or hunted to obtain their capes to make items of clothing. As of 2008, proposals have been made for

392-424: A giant pangolin/ edentate . In 1849, Henri Marie Ducrotay de Blainville described chalicothere skull remains from Sansan as belonging to the ungulate genus Anoplotherium (an extinct even-toed ungulate now known to be unrelated to chalicotheres). It was only in 1890 that a complete chalicothere skeleton found at Sansan was described by Henri Filhol , showing the skulls/teeth and the postcranial remains belonged to

448-567: A new band forms in a new home range. Researchers from the University of the Free State in South Africa, while observing gelada during field studies, discovered that the monkeys were capable of "cheating" on their partners and covering up their infidelity. A nondominant male mates surreptitiously with a female, with both suppressing their normal mating cries so as not to be overheard. If discovered,

504-505: A relatively gorilla-like physique, including knuckle-walking on their flexible forelimbs, which bore long curved claws. Members of this subfamily possessed some of the longest forelimbs and shortest hindlimbs in relation to each other out of all extinct animals. Analysis of dental wear implies that most chalicotheriines fed on seeds and fruit. Their claws were likely used in a hook-like manner to pull down branches, suggesting they lived as bipedal browsers . Presence of chalicothere fossils

560-400: A reproductive unit for four to five years. While geladas have traditionally been considered to have a male-transfer society, many males appear to be likely to return and breed in their natal bands. Nevertheless, gelada males leave their natal units and try to take over a unit of their own. A male can take over a reproductive unit either through direct aggression and fighting or by joining one as

616-432: A similar hierarchical status. Females generally stay in their natal units for life; cases of females leaving are rare. Aggression within a reproduction unit, which is rare, is usually just between the females. Aggression is more frequent between members of different reproductive units and is usually started by females, but males and females from both sides can join and engage if the conflict escalates. Males can remain in

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672-470: A subordinate and taking some females with him to create a new unit. When more than one male is in a unit, only one of them can mate with the females. The females in the group together can have power over the dominant male. When a new male tries to take over a unit and overthrow the resident male, the females can choose to support or oppose him. The male maintains his relationship with the females by grooming them rather than forcing his dominance, in contrast to

728-784: A term which is also applied to the broader grouping of Chalicotherioidea . They are noted for their unusual morphology compared to other ungulates, such as their clawed forelimbs. Members of the subfamily Chalicotheriinae developed elongate gorilla-like forelimbs that are thought to have been used to grasp vegetation. They are thought to have been browsers on foliage as well as possibly bark and fruit. The earliest remains chalicotheres were discovered were ungual phalanges found near Eppelsheim , Germany in early 19th century. These remains were considered to belong to gigantic pangolins by Georges Cuvier in 1822 while Johann Jakob Kaup in 1833 alternatively attributed them to deinotheres . Also in 1833, Kaup described chalicothere teeth as belonging to

784-440: A tuft of hair. Adult males have a long, heavy cape of hair on their backs. The gelada has a hairless face with a short muzzle that looks more similar to a chimpanzee's than a baboon's. It can also be physically distinguished from a baboon by the bright patch of skin on its chest. This patch is hourglass-shaped . On males, it is bright red and surrounded by white hair; on females, it is far less pronounced, but when in estrus ,

840-503: A variety of forest, woodland, and savannah habitats in Asia, Africa, and North America. They developed long necks and skull adaptations that suggest they had long, extensible tongues to reach browse, like those of giraffes . Strong hindlimbs and an elongated pelvis suggest they could have reared upright as modern goats do, and used their front claws to pull branches within reach of the tongue. The claws were retractable, and they walked normally on

896-500: Is 50–75 cm (19.7–29.5 in) for both sexes. Tail length is 30–50 cm (11.8–19.7 in). The gelada has several adaptations for its terrestrial and graminivorous (grass-eating) lifestyle. It has small, sturdy fingers adapted for pulling grass and narrow, small incisors adapted for chewing it. The gelada has a unique gait, known as the shuffle gait, that it uses when feeding. It squats bipedally and moves by sliding its feet without changing its posture. Because of this gait,

952-489: Is a stub . You can help Misplaced Pages by expanding it . Gelada The gelada ( Theropithecus gelada , Amharic : ጭላዳ , romanized :  č̣əlada , Oromo : Jaldeessa daabee ), sometimes called the bleeding-heart monkey or the gelada baboon , is a species of Old World monkey found only in the Ethiopian Highlands , living at elevations of 1,800–4,400 m (5,900–14,400 ft) above sea level. It

1008-650: Is also known from fossil specimens found in Africa and the Mediterranean into Asia, including South Africa, Malawi, the Democratic Republic of the Congo, Tanzania, Uganda, Kenya, Algeria, Morocco, Spain, and India (more exactly at Mirzapur , Cueva Victoria, Pirro Nord, Ternifine, Hadar , Turkana , Makapansgat , and Swartkrans ). The two subspecies of gelada are: The gelada has been referred to by other names, including

1064-413: Is carried on its mother's belly for the first five weeks, and thereafter on her back. Infants can move independently at around five months old. A subordinate male in a reproductive unit may help care for an infant when it is six months old. When herds form, juveniles and infants may gather into play groups of around 10 individuals. When males reach puberty, they gather into unstable groups independent of

1120-546: Is generally regarded as an indicator of forested environments. Unlike schizotheriines, chalicotheriines were typically confined to moist forests with a full tree canopy, and their lower-crowned teeth indicate a softer diet. While their appearance may look odd for an ungulate with a horse-like head, similar forms have evolved repeatedly in unrelated lineages: large herbivores that feed as bipedal browsers, standing or sitting upright and pulling down branches or stripping vegetation with clawed forelimbs. Examples include therizinosaurs ,

1176-450: Is the least-supported scenario in recent studies, i "gelada baboon" and other names implying a close relationship with baboons, with increasing clarity, are not scientifically justified, leading researchers to advocate for the common name to be simply "gelada". The gelada is large and robust, and it is covered with buff to dark-brown, coarse hair and has a dark face with pale eyelids. Its arms and feet are nearly black. Its short tail ends in

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1232-505: Is the only living member of the genus Theropithecus , a name derived from the Greek root words for "beast-ape" (θηρο-πίθηκος : thēro-píthēkos). Like its close relatives in genus Papio , the baboons , it is largely terrestrial , spending much of its time foraging in grasslands , with grasses comprising up to 90% of its diet. It has buff to dark brown hair with a dark face and pale eyelids. Adult males have longer hair on their backs and

1288-485: Is thought to be near that of humans. They sit around and chatter at each other, signifying to those around that they matter, in a way, to the individual "speaking". To some extent, calls are related to the status of an individual. In addition, females have calls signaling their estrus. Geladas communicate through gestures, as well. They display threats by flipping their upper lips back on their nostrils to display their teeth and gums, and by pulling back their scalps to display

1344-515: The brontotheres as the most distantly related within the order Perissodactyla . Chalicotheres can be first identified with certainty around 46 million years ago, in the Eocene of Asia. The family is thought to have evolved there, but appeared in North America by the Eocene. By the late Oligocene , they had divided into schizotheriines and chalicotheriines. (Earlier chalicotheres are often referred to

1400-499: The "gelada baboon", "bleeding-heart baboon", or simply "baboon", implying a monophyletic relationship with baboons, which historically included (apart from Theropithecus ) the genera Papio (true baboons), and Mandrillus (mandrills and drills). Since the 1990s, however, molecular phylogenetic studies clarified relationships among papionin monkeys, demonstrating that mangabeys of the genus Lophocebus are more closely related to Papio and Theropithecus , while mangabeys of

1456-491: The Arsi region of Ethiopia, which may be an incentive for females to abort and avoid investing caring for an infant that will most likely be killed. Infanticide in geladas remains fairly uncommon, though, compared to many primates that live in one-male units such as gorillas or gray langurs . The females that cancel their pregnancy are thought to bond with the new leader faster. When a male loses his position as dominant harem master,

1512-601: The Early Pleistocene of China. Chalicotheriinae Chalicotheriines are one of the two subfamilies of the extinct family Chalicotheriidae , a group of herbivorous , odd-toed ungulate (perissodactyl) mammals that lived from the Eocene to the Pleistocene. The other subfamily is the Schizotheriinae . Chalcotheriines evolved unique characteristics for ungulates, with very long forelimbs, short hindlimbs, and

1568-586: The bottom of the foot. Studies of tooth wear suggest they ate leaves, twigs, fruit, and bark. Chalicotheriines, such as Anisodon , lived only in moist, closed-canopy forests, never reached the Americas, and developed very unusual anatomy for an ungulate. Their shorter necks and horse-like heads did not show adaptations to reach high. Instead, they developed very long forelimbs with mobile shoulder joints and hooklike claws. The pelvis and hindlimbs were specialized to stand upright, and to sit for hours while feeding, like

1624-535: The chalicotheres declined from the late Neogene onwards, disappearing from North America and Europe by end of the Miocene . The youngest chalicotheres are the chalicotheriines Hesperotherium from the Early Pleistocene of China, Nestoritherium from the Early Pleistocene of Myanmar, as well as the schizotheriine Ancylotherium from the Early Pleistocene of Eastern and Southern Africa, also possibly known from

1680-400: The discovery of the kipunji . Nevertheless, the most recent and extensive phylogenetic study to date demonstrates that, while large fractions of the genome show an alternative history, the dominant relationship across the genome supports a closer relationship between Papio and Lophocebus , with Theropithecus as the outgroup. As a close sister relationship between Papio and Theropithecus

1736-433: The dominant male attacks the miscreants in a clear form of punishment. It is the first time that evidence of the knowledge of cheating and fear of discovery have been recorded among animals in the wild. Dr. Aliza le Roux of the university's Department of Zoology and Entomology believes that dishonesty and punishment are not uniquely human traits, and that the observed evidence of this behaviour among gelada monkeys suggests that

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1792-424: The early Miocene of North America, and the chalicotheriine Anisodon from the middle Miocene of Europe. Fossils of other species range from very fragmentary to moderately complete. Chalicotheres ranged in size from an antelope to a large draft horse. Chalicotheres are part of the order Perissodactyla , which includes modern equines , rhinoceroses , and tapirs , as well as extinct relatives like brontotheres . As

1848-500: The early evolution of perissodactyls is still unresolved, their closest relatives among other perissodactyl groups is obscure. They are generally placed as part of the clade Ancylopoda alongside their close relatives Lophiodontidae . Many studies considered them as closer to Ceratomorpha (which includes tapirs and rhinoceroses) than Equoidea. A 2004 cladistic study alternatively recovered Ancylopoda as sister to all modern perissodactyls (which includes Equoidea and Ceratomorpha), with

1904-568: The family Eomoropidae; it is not yet clear whether they had claws or how the two subfamilies diverged.) Both subfamilies were successful over many millions of years, and reached their greatest diversity in the Miocene. Advanced schizotheriines ( Moropus ) entered North America via the Bering land bridge at the Oligicene-Miocene boundary, and expanded southward into Central America. Never common animals,

1960-504: The female's patch brightens, and a "necklace" of fluid-filled blisters forms on the patch. This is thought to be analogous to the swollen buttocks common to most baboons experiencing estrus. In addition, females have knobs of skin around their patches. Geladas also have well developed ischial callosities . Sexual dimorphism is seen in this species; males average 18.5 kg (40.8 lb), while females are smaller, averaging 11 kg (24.3 lb). The head and body length of this species

2016-455: The females and new leader may allow him to remain in the social unit as a nonbreeding resident to act as a babysitter. This way, the ex-leader can protect any infants he had fathered from being killed by the new leader, the females can protect the infants fathered by him, and when the new leader faces a potential rival, the ex-leader will be more inclined to help support him in keeping rivals at bay. Mortality among infants occurs at its highest in

2072-554: The gelada is customarily placed in its own genus ( Theropithecus ), though some genetic research suggests that this monkey should be grouped with its baboon (genus Papio ) kin; other researchers have classified the species even more distantly from Papio . While Theropithecus gelada is the only living species of its genus, separate, larger species are known from the fossil record: T. brumpti , T. darti and T. oswaldi , formerly classified under genus Simopithecus . Theropithecus , while restricted at present to Ethiopia ,

2128-549: The gelada's rump is hidden beneath, so is unavailable for display; its bright red chest patch is visible, though. Geladas are found only in the high grasslands of the deep gorges of the central Ethiopian plateau. They live in elevations 1,800–4,400 m (5,900–14,400 ft) above sea level, using the cliffs for sleeping and montane grasslands for foraging. These grasslands have widely spaced trees and also contain bushes and dense thickets. The highland areas where they live tend to be cooler and less arid than lowland areas. Thus,

2184-432: The geladas always fled great distances to the cliffs for safety whenever they encountered aggressive domestic dogs. When in estrus, the female points her posterior towards a male and raises it, moving her tail to one side. The male then approaches the female and inspects her chest and genital areas. A female will copulate up to five times per day, usually around midday. Breeding and reproduction can occur at any time of

2240-457: The geladas usually do not experience the negative effects that the dry season has on food availability. Nevertheless, in some areas, they do experience frost in the dry season, as well as hailstorms in the wet season. Geladas are the only primates that are primarily graminivores and grazers – grass blades make up to 90% of their diet. They eat both the blades and the seeds of grasses. When both blades and seeds are available, geladas prefer

2296-485: The genus Cercocebus are more closely related to Mandrillus . These findings largely invalidated any scientifically based justification for referring to mandrills and drills as baboons, as doing so while excluding the unbaboon-like Lophocebus mangabeys would create a polyphyletic group. The status of geladas was less clear and the relationships among Papio , Lophocebus , and Theropithecus continue to reflect high levels of uncertainty, which are further complicated by

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2352-436: The group before attempting to join a reproductive unit. All-male groups are generally aggressive towards both reproductive units and other all-male units. As in reproductive units, aggression within all-male units is rare. As bands, reproductive units exist in a common home range. Within the band, members are closely related and between the units there is no social hierarchy. Bands usually break apart every eight to nine years as

2408-488: The ledges of cliffs. At sunrise, they leave the cliffs and travel to the tops of the plateaus to feed and socialize. When morning ends, social activities tend to wane and the geladas primarily focus on foraging. They travel during this time, as well. When evening arrives, they exhibit more social activities before descending to the cliffs to sleep. Predators observed to hunt geladas include domestic dogs , leopards , servals , hyenas , and lammergeiers . Geladas live in

2464-522: The living gelada monkey. Some early paleontologists thought the claws were used to dig up roots and tubers, but their teeth were designed for soft foods, and studies of tooth wear show they ate fruit and seeds. Their forelimbs were specialized to reach, grasp, and strip or sweep plants to the mouth. They could not retract the huge front claws, and knuckle-walked on their forelimbs. The chalicotheriines' anatomical design, posture, and locomotion show convergence with other large browsers that feed selectively in

2520-476: The new genus Chalicotherium from the same locality, which he did not recognise as belonging to the same species as the ungual phalanges. Beginning in the 1930s, the Sansan deposit in southern France was excavated for fossils, yielding remains of chalicotheres. In 1837, postcranial remains from the deposit were given the name " Macrotherium" by Édouard Lartet , who like Cuvier thought the remains represented those of

2576-483: The new male. When more than one male is in the unit, only one can mate with the females. The gelada has a diverse repertoire of vocalizations thought to be near in complexity to that of humans. The population of geladas is thought to have dropped from 440,000 in the 1970s to 200,000 in 2008. Despite the heavy loss, it is listed as least concern by the International Union for Conservation of Nature . Since 1979,

2632-438: The pale eyelids. A gelada submits by fleeing or presenting itself. In 2016, a research group at the University of Michigan found that gelada vocalizations obey Menzerath's law , observing that calls are abbreviated when used in longer sequences. The gelada is considered a crop pest by farmers near Simien National Park . In 2005, they caused an average of 100 kg (220 lb) of crop damage per animal. The geladas had

2688-551: The pantodont Barylambda , homalodotheres , and megatheriid ground sloths. Anisodon shows ischial callosities on the pelvis, a characteristic adaptation for sitting for long periods of time. Chalicotheriines are likely to have diverged as specialist feeders sitting in lush forests, similar to modern gorillas and giant pandas. This article related to the Neogene period is a stub . You can help Misplaced Pages by expanding it . This prehistoric odd-toed ungulate -related article

2744-550: The reproductive units, the females tend to be closely related and have strong social bonds. Reproductive units split if they become too large. While females have strong social bonds in the group, a female only interacts with at most three other members of her unit. Grooming and other social interactions among females usually occur between pairs. Females in a reproductive unit exist in a hierarchy, with higher-ranking females having more reproductive success and more offspring than lower-ranking females. Closely related females tend to have

2800-554: The reproductive units. Females sexually mature at around three years, but do not give birth for another year. Males reach puberty at about four to five years, but they are usually unable to reproduce because of social constraints and wait until they are about eight to ten years old. Average lifespan in the wild is 15 years. Adult geladas use a diverse repertoire of vocalizations for various purposes, such as: contact, reassurance, appeasement, solicitation, ambivalence, aggression, and defense. The level of complexity of these vocalizations

2856-462: The roots of the human system of deceit, crime, and punishment lie very deep indeed. Mixed-species association was observed between solitary Ethiopian wolves and geladas. According to the study's findings, gelada monkeys typically do not move on encountering Ethiopian wolves, even when they were in the middle of the herd; 68% of encounters resulted in no movement and only 11% resulted in a movement greater than 10 m (33 ft). In stark contrast,

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2912-548: The same unusual animal. Unlike modern perissodactyls, chalicotheres had clawed feet. They had, lower incisors that cropped food against a toothless pad in the upper jaw, low-crowned molar teeth, and were browsers on trees and shrubs throughout their history. They evolved in two different directions, which became separate subfamilies, the Schizotheriinae and the Chalicotheriinae . Schizotherine chalicotheres such as Moropus had relatively equal length limbs, and lived in

2968-503: The seeds. They eat flowers, rhizomes , and roots when available, using their hands to dig for the latter two. They consume herbs, small plants, fruits, creepers, bushes, and thistles. Insects can be eaten, but only rarely and only if they can easily be obtained. During the dry season, herbs are preferred over grasses. Geladas consume their food more like ungulates than primates, and they can chew their food as effectively as zebra . Geladas are primarily diurnal . At night, they sleep on

3024-485: The society of the hamadryas baboon. Females accept a male into the unit by presenting themselves to him. Not all the females may interact with the male. Usually, one may be his main partner. The male may sometimes be monopolized by this female. The male may try to interact with the other females, but they are usually unresponsive. Most all-male units consist of several subadults and one young adult, led by one male. A member of an all-male unit may spend two to four years in

3080-412: The wet season, but on average, over 85% of infants survive to their fourth birthday, one of the great advantages of living in an environment with a food source few other animals can exploit, so is unable to sustain many large predators. Females that have just given birth stay on the periphery of the reproductive unit. Other adult females may take an interest in the infants and even kidnap them. An infant

3136-600: The year, although some areas have birth peaks. Most births occur at night. Newborn infants have red faces and closed eyes, and they are covered in black hair. On average, newborn infants weigh 464 g (16.4 oz). If a new male assumes mastery of a harem, females impregnated by the previous leader have an 80% likelihood of aborting, in a phenomenon known as the Bruce effect . Females come into estrus quickly after giving birth, so males have little incentive for practising infanticide, although it does occur in some communities in

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