Hominids[1] Temporal range: 7–0 Ma PreЄ Є O S D C P T J K Pg N Late Miocene to Recent
Australopithecus africanus reconstruction
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Primates
Suborder:	Haplorrhini
Infraorder:	Simiiformes
Parvorder:	Catarrhini
Superfamily:	Hominoidea
Family:	Hominidae Gray, 1825
Genera
Subfamily Ponginae Pongo – orangutans Subfamily Homininae Gorilla – gorillas Homo – humans Pan – chimpanzees
Synonyms
Pongidae Elliot, 1913

The Hominidae ( /hɒˈmɪnɨdiː/; anglicized hominids, also known as great apes^{[notes 1]}), as the term is used here, form a taxonomic family, including four extant genera: chimpanzees (Pan), gorillas (Gorilla), humans (Homo), and orangutans (Pongo).^[1] The term "hominid" is also used in the more restricted sense of humans and relatives of humans closer than chimpanzees.^[2] In this usage, all hominid species other than Homo sapiens are extinct.

A number of known extinct genera are grouped with humans in the Homininae subfamily, others with orangutans in the Ponginae subfamily. The most recent common ancestor of the Hominidae lived roughly 14 million years ago,^[3] when the ancestors of the orangutans speciated from the ancestors of the other three genera.^[4] The ancestors of the Hominidae family had already speciated from those of the Hylobatidae family, perhaps 15 million to 20 million years ago.^[4][5]

Family tree showing the extant hominoids: humans (genus Homo), chimpanzees and bonobos (genus Pan), gorillas (genus Gorilla), orangutans (genus Pongo), and gibbons (four genera of the family Hylobatidae: Hylobates, Hoolock, Nomascus, and Symphalangus). All except gibbons are hominids.

History[link]

On July 19, 2001, a 7-million-year-old fossil skull, classified as Sahelanthropus tchadensis and nicknamed "Toumaï", was discovered in Chad, Africa. It is possibly the earliest hominine fossil ever found. In addition to its age, Toumaï, unlike the three- to four-million-year younger gracile australopithecine dubbed "Lucy", has a relatively flat face without the prominent snout seen on other pre-Homo hominids.^[6] There is some dispute over the importance of Sahelanthropus tchadensis. It could be that this species is a direct ancestor of modern humans (or at least closely related to a direct ancestor). In the absence of additional fossil species from this era, certainty is impossible.^[7]

Sumatran orangutan (Pongo abelii)

Researchers, such as David Reich and Eric Lander, have found evidence that the divergence between proto-chimpanzees and proto-humans was marked by episodes of gene flow over millions of years, before the final separation.^[8] It is generally believed that the Pan/Homo separation occurred about 6 – 8 million years ago,^[9][10][11] but the molecular clock (a method of calculating evolution based on the rate at which genes mutate) suggests the genera division 4.6 – 6.2 million years ago.^[12] Previous studies looked at average genetic differences between human and chimp. The new study compares the ages of key sequences of genes of modern humans and modern chimps. Some sequences are younger than others, indicating that chimps and humans gradually separated over a period of 4 million years. The youngest human chromosome is the X chromosome which is about 1.2 million years more recent than the 22 autosomes.^[8] The X sex chromosome responds more quickly to selective pressure, which may explain the discrepancy.^[13] Its age suggests there was an initial division between the two species, followed by gradual divergence and interbreeding that resulted in younger genes, and then a final separation.

A minority viewpoint is that Homo diverged from a common ancestor with Pongo perhaps as early as 13 million years ago, so that Pan is more closely related to Gorilla. This alternative is supported by characteristics uniquely shared between humans and orangutans, such as dental structure, thick enamel, shoulder blade structure, thick posterior palate, single incisive foramen, high estriol production, and beard and mustache. There are at least 28 such well-corroborated features compared with perhaps as few as one unique feature shared between humans and chimpanzees. It is widely believed that these physical features are misleading, but an alternative possibility is that orangutans have undergone more genetic change than humans and African apes have since their divergence from the common ancestor. If this had happened, then the apparent genetic similarity between humans and chimpanzees would not necessarily be due to a close evolutionary relationship.^[14][15] This hypothesis has been proposed as an explanation as to why early hominids, such as the australopiths, not only look more like orangutans than modern African apes, but also share characters unique to orangutans and their close fossil relatives, such as a thickened posterior palate and anterior zygomatic roots.^[16]

Taxonomic history[link]

Humans are one of the four extant hominid genera.

The classification of the great apes has been revised several times in the last few decades. These various revisions have led to a varied use of the word "hominid" – the original meaning of Hominidae referred only to the modern meaning of Hominina, i.e. only humans and their closest relatives. The meaning of the taxon changed gradually, leading to the modern meaning of "hominid", which includes all great apes and humans.

A model of a modern human hominid skull

A Fossil Hominid Exhibit at The Museum of Osteology, Oklahoma City, Oklahoma

The primatological term hominid is easily confused with a number of very similar words:

• A hominoid, commonly called an ape, is a member of the superfamily Hominoidea: extant members are the lesser apes (gibbons) and great apes (hominids).
• A hominine is a member of the subfamily Homininae: gorillas, chimpanzees, humans (excludes orangutans).
• A hominin is a member of the tribe Hominini: bonobos, chimpanzees and humans.
• A hominan is a member of the subtribe Hominina: modern humans and their extinct relatives.
• A human is a member of the genus Homo, of which Homo sapiens is the only extant species, and within that Homo sapiens sapiens is the only surviving subspecies.

Many scientists, including anthropologists, continue to use the term hominid to mean humans and their direct and near-direct bipedal ancestors.

As mentioned, Hominidae was originally the name given to humans and their extinct relatives, with the other great apes being placed in a separate family, the Pongidae. However, that definition made Pongidae paraphyletic because at least one great ape species appears to be more closely related to humans than to other great apes. Most taxonomists nowadays encourage monophyletic groups – this would require the use of Pongidae to be restricted to one of the great ape groups (containing Pongo, the orangutans) only. Thus, many biologists consider Hominidae to include Pongidae as the subfamily Ponginae, or restrict the latter to the orangutans and their extinct relatives, such as Gigantopithecus. The taxonomy shown here follows the monophyletic groupings according to the two theories of human and great ape relationships.

Especially close human relatives form a subfamily, the Homininae. A few researchers go so far as to include chimpanzees^[17] and gorillas^[18][19] in the genus Homo along with humans. Alternatively, those fossil relatives more closely related to humans than the nearest living great ape species represent members of Hominidae without necessarily assigning subfamily or tribal categories. If the orangutan is the closest living relative of humans, there would be a sister group relationship between Hominidae and Pongidae, with the African apes comprising a separate family (Panidae) according to the morphological evidence.^[15][20]

Many extinct hominids have been studied to help understand the relationship between modern humans and the other extant hominids. Some of the extinct members of this family (as defined to encompass humans and chimpanzees) include Gigantopithecus, Orrorin, Ardipithecus, Kenyanthropus, and the australopithecines Australopithecus and Paranthropus. In the orangutan model of human origin, the Hominidae would include the australopiths, and possibly Orrorin and Kenyanthropus, but not Ardipithecus and Sahelanthropus that lack features necessary to provide strong corroboration as hominids.^[21]

The exact criteria for membership in the Homininae under the chimpanzee theory of human origins are not clear, but the subfamily generally includes those species that share more than 97% of their DNA with the modern human genome, and exhibit a capacity for language or for simple cultures beyond the family or band. The theory of mind including such faculties as mental state attribution, empathy and even empathetic deception is a controversial criterion distinguishing the adult human alone among the hominids. Humans acquire this capacity at about four and a half years of age, whereas it has neither been proven nor disproven that gorillas and chimpanzees develop a theory of mind.^[22] This is also the case for some New World monkeys outside the family of great apes, as, for example, the capuchin monkeys.

However, without the ability to test whether early members of the Homininae (such as Homo erectus, Homo neanderthalensis, or even the australopithecines) had a theory of mind, it is difficult to ignore similarities seen in their living cousins. Orangutans have also been shown to have culture comparable to that of chimpanzees,^[23] and some say the orangutan may also satisfy these criteria. These scientific debates take on political significance for advocates of Great Ape personhood.

Classification[link]

Skulls of an orangutan and a gorilla

The seven living species of great ape are classified in four genera. The following classification is commonly accepted:^[1]

• Family Hominidae: humans and other great apes; extinct genera and species excluded^[1]
  • Subfamily Ponginae
    • Genus Pongo
      • Bornean orangutan, Pongo pygmaeus
        • Pongo pygmaeus pygmaeus
        • Pongo pygmaeus morio
        • Pongo pygmaeus wurmbii
      • Sumatran orangutan, Pongo abelii
  • Subfamily Homininae
    • Tribe Gorillini
      • Genus Gorilla
        • Western gorilla, Gorilla gorilla
          • Western lowland gorilla, Gorilla gorilla gorilla
          • Cross River gorilla, Gorilla gorilla diehli
        • Eastern gorilla, Gorilla beringei
          • Mountain gorilla, Gorilla beringei beringei
          • Eastern lowland gorilla, Gorilla beringei graueri
    • Tribe Hominini
      • Genus Pan
        • Common chimpanzee, Pan troglodytes
          • Central chimpanzee, Pan troglodytes troglodytes
          • West African chimpanzee, Pan troglodytes verus
          • Nigerian chimpanzee, Pan troglodytes ellioti
          • Eastern chimpanzee, Pan troglodytes schweinfurthii
        • Bonobo (pygmy chimpanzee), Pan paniscus
      • Genus Homo
        • Human, Homo sapiens sapiens

In addition to the extant species and subspecies above, archaeologists, paleontologists, and anthropologists have discovered numerous extinct great ape species. The list below are some of the genera of those discoveries.^[1]

• Subfamily Ponginae (or Pongidae)
  • Gigantopithecus†
  • Sivapithecus†
  • Lufengpithecus†
  • Ankarapithecus†
  • Ouranopithecus†
• Subfamily Homininae (or Hominidae)
  • Homo – immediate ancestors of modern humans
    • Homo habilis†
    • Homo rudolfensis†
    • Homo ergaster†
    • Homo georgicus†
    • Homo erectus†
    • Homo cepranensis†
    • Homo antecessor†
    • Homo heidelbergensis†
    • Homo rhodesiensis†
    • Homo neanderthalensis†
    • Homo sapiens
      • Homo sapiens idaltu†
      • Archaic Homo sapiens (Cro-magnon)†
    • Homo floresiensis†
  • Dryopithecus†
  • Oreopithecus†(hominid status disputed)
  • Paranthropus†
  • Australopithecus†
  • Sahelanthropus†(hominid status highly problematic)
  • Orrorin†
  • Ardipithecus†
  • Kenyanthropus†

Physical description[link]

The great apes are large, tailless primates, with the smallest living species being the bonobo at 30–40 kilograms in weight, and the largest being the gorillas, with males weighing 140–180 kilograms. In all great apes, the males are, on average, larger and stronger than the females, although the degree of sexual dimorphism varies greatly among species. Although most living species are predominantly quadrupedal, they are all able to use their hands for gathering food or nesting materials, and, in some cases, for tool use.^[24]

Most species are omnivorous, but fruit is the preferred food among all but humans. Chimpanzees and orangutans primarily eat fruit. When gorillas run short of fruit at certain times of the year or in certain regions, they resort to eating shoots and leaves, often of bamboo, a type of grass. Gorillas have extreme adaptations for chewing and digesting such low-quality forage, but they still prefer fruit when it is available, often going miles out of their way to find especially preferred fruits. Humans, since the neolithic revolution, consume mostly cereals and other starchy foods, including increasingly highly processed foods, as well as many other domesticated plants (including fruits) and meat. Hominid teeth are similar to those of the Old World monkeys and gibbons, although they are especially large in gorillas. The dental formula is:Failed to parse (Missing texvc executable; please see math/README to configure.): \tfrac{ 2.1.2.3}{ 2.1.2.3}

Human teeth and jaws are markedly smaller for their size than those of other apes, which may be an adaptation to eating cooked food for more than a million years.[25][26]

Gorilla

Gestation in great apes lasts 8–9 months, and results in the birth of a single offspring, or, rarely, twins. The young are born helpless, and they must be cared for, for long periods of time. Compared with most other mammals, great apes have a remarkably long adolescence, not being weaned for several years, and not becoming fully mature for eight to thirteen years in most species (longer in humans). As a result, females typically give birth only once every few years. There is no distinct breeding season.^[24]

Gorillas and chimpanzees live in family groups of around five to ten individuals, although much larger groups are sometimes noted. Chimpanzees live in larger groups that break up into smaller groups when fruit becomes less available. When small groups of female chimpanzees go off in separate directions to forage for fruit, the dominant male(s) can no longer control them and the females often mate with other subordinate males, whether by choice or not. In contrast, groups of gorillas stay together regardless of the availability of fruit. When fruit is hard to find, they resort to eating leaves and shoots. Because gorilla groups stay together, the male is able to monopolize the females in his group. This fact is related to gorillas' greater sexual dimorphism than chimpanzees'. In both chimpanzees and gorillas, the groups include at least one dominant male, and females leave the group at maturity.

Legal status[link]

Due to the close genetic relationship between humans and other great apes, certain animal rights organizations, such as the Great Ape Project, argue that nonhuman great apes are persons and should be given basic human rights. Some countries have instituted a research ban to protect great apes from any kind of scientific testing.

On 25 June 2008, the Spanish parliament supported a new law that would make "keeping apes for circuses, television commercials or filming" illegal.^[27]

See also[link]

• Great ape language
  • The Mind of an Ape
• Primate cognition
• List of apes – notable individual apes
• Ape extinction
  • Great Apes Survival Project
  • Kinshasa Declaration on Great Apes
• Homininae
• Human evolution
  • Timeline of human evolution
• Great Ape Project

Notes[link]

References[link]

External links[link]

Wikimedia Commons has media related to: Hominidae

Wikispecies has information related to: Hominidae

The Wikibook Dichotomous Key has a page on the topic of Hominidae

• Renderings of Hominid Exemplars at the Smithsonian
• Additional information on great apes
• NPR News: Toumaï the Human Ancestor
• Hominid Species at TalkOrigins Archive
• For more details on Hominid species, including excellent photos of fossil hominids
• New Scientist 19 May 2003 – Chimps are human, gene study implies
• Scientific American Magazine (April 2006 Issue) Why Are Some Animals So Smart?
• A new mediterranean hominoid-hominid link discovered, Anoiapithecus brevirostris, "Lluc": A unique Middle Miocene European hominoid and the origins of the great ape and human clade Link to graphical reconstruction

v t e Ape-related articles Ape species Human Bonobo Common chimpanzee Gorilla Orangutan Gibbon Ape study Ape language Great Ape Trust Dian Fossey Birutė Galdikas Jane Goodall Chimpanzee genome project Human genome project Neanderthal genome project Willie Smits Lone Drøscher Nielsen Borneo Orangutan Survival Legal and social status Personhood Research ban Kinshasa Declaration Great Ape Project Survival Project See also List of apes (non-human) Bushmeat Ape extinction List of fictional primates Human evolution Mythic humanoids Hominid

Look up great or greatness in Wiktionary, the free dictionary.

Great may refer to:

• Greatness, being superior, majestic, transcendent, or divine
• GReAT, Graph Rewriting and Transformation, a Model Transformation Language
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• Great (supermarket), a supermarket in Hong Kong

See also[link]

• All pages beginning with "Great"
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Hominoidea Temporal range: Late Oligocene - Recent
Lar Gibbon (Hylobates lar)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Primates
Suborder:	Haplorrhini
Infraorder:	Simiiformes
Parvorder:	Catarrhini
Superfamily:	Hominoidea Gray, 1825
Families
†Pliopithecidae †Proconsulidae Hylobatidae †Oreopithecidae Hominidae

Apes are Old World anthropoid mammals, more specifically a clade of tailless catarrhine primates, belonging to the biological superfamily Hominoidea. The apes are native to Africa and South-east Asia. Apes are the largest primates and the orangutan, an ape, is the largest living arboreal animal. Hominoids are traditionally forest dwellers, although chimpanzees may range into savanna, and the extinct australopithecines are famous for being savanna inhabitants, inferred from their morphology. Humans inhabit almost every terrestrial habitat.

Hominoidea contains two families of living (extant) species:

• Hylobatidae consists of four genera and sixteen species of gibbon, including the lar gibbon and the siamang. They are commonly referred to as lesser apes.
• Hominidae consists of orangutans, gorillas, chimpanzees, bonobos and humans.^[1][2] Alternatively, the hominidae family are collectively described as the great apes.^[3][4][5][6]

Members of the superfamily are called hominoids (not to be confused with "hominids" or "hominins").

Some or all hominoids are also called "apes". However, the term "ape" is used in several different senses. It has been used as a synonym for "monkey" or for any tailless primate with a humanlike appearance.^[7] Thus the Barbary macaque, a kind of monkey, is popularly called the "Barbary ape" to indicate its lack of a tail. Biologists have used the term "ape" to mean a member of the superfamily Hominoidea other than humans,^[3] or more recently to mean all members of the superfamily Hominoidea, so that "ape" becomes another word for "hominoid".^[6][8] See also Primate: Historical and modern terminology.

Except for gorillas and humans, hominoids are agile climbers of trees. Their diet is best described as vegetarian or omnivorous, consisting of leaves, nuts, seeds and fruits, including grass seeds, and in most cases other animals, either hunted or scavenged (or farmed in the case of humans), along with anything else available and easily digested.

Most nonhuman hominoids are rare or endangered. The chief threat to most of the endangered species is loss of tropical rainforest habitat, though some populations are further imperiled by hunting for bushmeat.

Historical and modern terminology[link]

"Ape", from Old English apa, is possibly an onomatopoetic imitation of animal chatter. The term has a history of rather imprecise usage. Its earliest meaning was a tailless (and therefore exceptionally human-like) nonhuman primate.^[7] The original usage of "ape" in English might have referred to the baboon, an Old World monkey.^{[citation needed]} Two tailless species of macaque have common names including "ape": the Barbary ape of North Africa (introduced into Gibraltar), Macaca sylvanus, and the Sulawesi black ape or Celebes crested macaque, M. nigra.

As zoological knowledge developed, it became clear that taillessness occurred in a number of different and otherwise unrelated species. The term "ape" was then used in two different senses, as shown in the 1910 Encyclopædia Britannica entry. Either "ape" was still used for a tailless humanlike primate or it became a synonym for "monkey".^[7]

Sir Wilfrid Le Gros Clark was one of the primatologists who developed the idea that there were "trends" in primate evolution and that the living members of the order could be arranged in a series, leading through "monkeys" and "apes" to humans. Within this tradition, "ape" refers to all the members of the superfamily Hominoidea, except humans.^[3] Thus "apes" are a paraphyletic group, meaning that although all the species of apes descend from a common ancestor, the group does not include all the descendants of that ancestor, because humans are excluded.^[9] The diagram below shows the currently accepted evolutionary relationships of the Hominoidea,^[2] with the apes marked by a bracket.

The "apes" are traditionally divided further into the "lesser apes" and the "great apes":^[10]

In summary, there are three common uses of the term "ape": non-biologists may not distinguish between "monkeys" and "apes", or may use "ape" for any tailless monkey or nonhuman hominoid, whereas biologists traditionally used the term "ape" for all non-human hominoids as shown above.

In recent years biologists have generally preferred to use only monophyletic groups in classifications,^{[citation needed]} that is only groups which include all the descendants of a common ancestor.^[11] The superfamily Hominoidea is one such group (or "clade"). Some then use the term "ape" to mean all the members of the superfamily Hominoidea. For example, in a 2005 book, Benton wrote "The apes, Hominoidea, today include the gibbons and orang-utan ... the gorilla and chimpanzee ... and humans".^[6] The group traditionally called "apes" by biologists is then called the "nonhuman apes".

See the section History of hominoid taxonomy below for a discussion of changes in scientific classification and terminology.

Biology[link]

This unreferenced section requires citations to ensure verifiability.

The "lesser apes" are the gibbon family, Hylobatidae with sixteen medium-sized species. Their major differentiating characteristic is their long arms, which they use to brachiate through the trees. As an evolutionary adaptation to this arboreal lifestyle, their wrists are ball and socket joints. The largest of the gibbons, the siamang, weighs up to 14 kg (31 lb). In comparison, the smallest "great ape" is the common chimpanzee at 40 to 65 kg (88 to 143 lb).

The "great apes" were formerly treated as the family Pongidae. As noted above, this definition makes the Pongidae paraphyletic, and does not show that orangutans, gorillas, chimpanzees and humans are all more closely related to one another than any of these four groups are to gibbons. Further, current evidence implies that humans share a common extinct ancestor with the chimpanzee line, from which we separated more recently than the gorilla line.

The superfamily Hominoidea falls within Catarrhini, which also includes the Old World monkeys of Africa and Eurasia. Within this group, both families (Hylobatidae and Hominidae) can be distinguished from Old World monkeys by the number of cusps on their molars (hominoids have five—the "Y-5" molar pattern, Old World monkeys have only four in a bilophodont pattern). Hominoids have more mobile shoulder joints and arms due to the dorsal position of the scapula, broad ribcages that are flatter front-to-back, and a shorter, less mobile spine compared to Old World monkeys, with caudal (tail) vertebrae greatly reduced, resulting in complete tail loss in living species. These are all anatomical adaptations to vertical hanging and swinging locomotion (brachiation), as well as better balance in a bipedal pose. However, there are also primates in other families that lack tails, and at least one (the pig-tailed langur) that has been known to walk significant distances bipedally. The front skull is characterised by its sinuses, fusion of the frontal bone and post-orbital constriction.

Although the hominoid fossil record is far from complete, and the evidence is often fragmentary, there is enough to give a good outline of the evolutionary history of humans. The time of the split between humans and other living hominoids used to be thought to have occurred 15 to 20 million years ago. Some species occurring within that time period, such as Ramapithecus, used to be considered as hominins, and possible ancestors of humans. Later fossil finds indicated that Ramapithecus was more closely related to the orangutan, and new biochemical evidence indicated that the last common ancestor of humans and other hominins occurred between 5 and 10 million years ago, and probably in the lower end of that range.

Behaviour and cognition[link]

This section needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (July 2011)

Although there had been earlier studies, the scientific investigation of behaviour and cognition in nonhuman members of the superfamily Hominoidea expanded enormously during the latter half of the twentieth century. Major studies of behaviour in the field were completed on the three better-known "great apes", for example by Jane Goodall, Dian Fossey and Birute Galdikas (field work on gibbons and the bonobo is still relatively underdeveloped). These studies have shown that in their natural environments, the nonhuman hominoids show sharply varying social structure: gibbons are monogamous, territorial pair-bonders, orangutans are solitary, gorillas live in small troops with a single adult male leader, while chimpanzees live in larger troops with bonobos exhibiting promiscuous sexual behaviour. Their diets also vary; gorillas are foliovores while the others are all primarily frugivores, although the common chimpanzee does some hunting for meat. Foraging behaviour is correspondingly variable.

All the nonhuman hominoids are generally thought of as highly intelligent, and scientific study has broadly confirmed that they perform outstandingly well on a wide range of cognitive tests – though there is relatively little data on gibbon cognition. The early studies by Wolfgang Köhler demonstrated exceptional problem-solving abilities in chimpanzees, which Köhler attributed to insight. The use of tools has been repeatedly demonstrated; more recently, the manufacture of tools has been documented, both in the wild and in laboratory tests. Imitation is much more easily demonstrated in "great apes" than in other primate species. Almost all the studies in animal language acquisition have been completed with "great apes", and though there is continuing dispute as to whether they demonstrate real language abilities, there is no doubt that they involve significant feats of learning. Chimpanzees in different parts of Africa have developed tools that are used in food acquisition, demonstrating a form of animal culture.^[12]

Distinction from monkeys[link]

Apes do not possess a tail, unlike most monkeys. Monkeys are more likely to be in trees and use their tails for balance. Apes are considerably larger than monkeys, with the exception of gibbons, which are smaller than some monkeys. Apes are considered to be more intelligent than monkeys, which are considered to have more primitive brains.^[13] Unlike female monkeys which go through the estrous cycle, great apes, including humans, go through a menstrual cycle.

History of hominoid taxonomy[link]

The history of hominoid taxonomy is somewhat confusing and complex. The names of subgroups have changed their meaning over time as new evidence, from fossil discoveries and comparisons of anatomy and DNA sequences, has changed understanding of the relationships between hominoids. There has been a gradual demotion of humans from a special position in the taxonomy to being one branch among many. This history illustrates the growing influence of cladistics (the science of classifying living things by strict descent) on taxonomy.

As of 2006, there are eight extant genera of hominoids. They are the four genera in the family Hominidae (Homo – humans, Pan – chimpanzees and bonobos, Gorilla, and Pongo – orangutans), and the four genera in the family Hylobatidae or gibbons (Hylobates, Hoolock, Nomascus and Symphalangus).^[1] (The genus for the hoolock gibbons was recently changed from Bunopithecus to Hoolock.^[14])

In 1758, Carolus Linnaeus, relying on second- or third-hand accounts, placed a second species in Homo along with H. sapiens: Homo troglodytes ("cave-dwelling man"). It is not clear to which animal this name refers, as Linnaeus had no specimen to refer to, hence no precise description. Linnaeus named the orangutan Simia satyrus ("satyr monkey"). He placed the three genera Homo, Simia and Lemur in the order of Primates.

The troglodytes name was used for the chimpanzee by Blumenbach in 1775 but moved to the genus Simia. The orangutan was moved to the genus Pongo in 1799 by Lacépède.

Linnaeus's inclusion of humans in the primates with monkeys and apes was troubling for people who denied a close relationship between humans and the rest of the animal kingdom. Linnaeus's Lutheran archbishop had accused him of "impiety." In a letter to Johann Georg Gmelin dated 25 February 1747, Linnaeus wrote:

It is not pleasing to me that I must place humans among the primates, but man is intimately familiar with himself. Let's not quibble over words. It will be the same to me whatever name is applied. But I desperately seek from you and from the whole world a general difference between men and simians from the principles of Natural History. I certainly know of none. If only someone might tell me one! If I called man a simian or vice versa I would bring together all the theologians against me. Perhaps I ought to, in accordance with the law of Natural History.^[15]

Accordingly, Johann Friedrich Blumenbach in the first edition of his Manual of Natural History (1779), proposed that the primates be divided into the Quadrumana (four-handed, i.e. apes and monkeys) and Bimana (two-handed, i.e. humans). This distinction was taken up by other naturalists, most notably Georges Cuvier. Some elevated the distinction to the level of order.

However, the many affinities between humans and other primates — and especially the "great apes" — made it clear that the distinction made no scientific sense. Charles Darwin wrote, in The Descent of Man:

The greater number of naturalists who have taken into consideration the whole structure of man, including his mental faculties, have followed Blumenbach and Cuvier, and have placed man in a separate Order, under the title of the Bimana, and therefore on an equality with the orders of the Quadrumana, Carnivora, etc. Recently many of our best naturalists have recurred to the view first propounded by Linnaeus, so remarkable for his sagacity, and have placed man in the same Order with the Quadrumana, under the title of the Primates. The justice of this conclusion will be admitted: for in the first place, we must bear in mind the comparative insignificance for classification of the great development of the brain in man, and that the strongly marked differences between the skulls of man and the Quadrumana (lately insisted upon by Bischoff, Aeby, and others) apparently follow from their differently developed brains. In the second place, we must remember that nearly all the other and more important differences between man and the Quadrumana are manifestly adaptive in their nature, and relate chiefly to the erect position of man; such as the structure of his hand, foot, and pelvis, the curvature of his spine, and the position of his head.^[16]

Changes in taxonomy[link]

Until about 1960, the hominoids were usually divided into two families: humans and their extinct relatives in Hominidae, all other hominoids in Pongidae.[17]
The 1960s saw the application of techniques from molecular biology to primate taxonomy. Goodman used his 1964 immunological study of serum proteins to propose a division of the hominoids into three families, with the "great apes" in Pongidae and the "lesser apes" (gibbons) in Hylobatidae.[18] The trichotomy of hominoid families, however, prompted scientists to ask which family speciated first from the common hominoid ancestor.
Within the superfamily Hominoidea, gibbons are the outgroup: this means that the rest of the hominoids are more closely related to each other than any of them are to gibbons. This led to the placing of the "great apes" into the family Hominidae along with humans, by demoting the Pongidae to a subfamily; the Hominidae family now contained the subfamilies Homininae and Ponginae. Again, the three-way split in Ponginae led scientists to ask which of the three genera is least related to the others.
Investigation showed orangutans to be the outgroup, but comparing humans to all three other hominid genera showed that African "apes" (chimpanzees and gorillas) and humans are more closely related to each other than any of them are to orangutans. This led to the placing of the African hominoids in the subfamily Homininae, forming another three-way split. This classification was first proposed by M. Goodman in 1974.[19]
To try to resolve the hominine trichotomy, some authors proposed the division of the subfamily Homininae into the tribes Gorillini (African "apes") and Hominini (humans).
However, DNA comparisons provide convincing evidence that within the subfamily Homininae, gorillas are the outgroup. This suggests that chimpanzees should be in Hominini along with humans. This classification was first proposed (though one rank lower) by M. Goodman et al. in 1990.[2] See Human evolutionary genetics for more information on the speciation of humans and "great apes".
Later DNA comparisons split the gibbon genus Hylobates into four genera: Hylobates, Hoolock, Nomascus, and Symphalangus.[1][14]

Classification and evolution[link]

As discussed above, hominoid taxonomy has undergone several changes. Genetic analysis shows that hominoids diverged from the Old World monkeys between 29 million and 34.5 million years ago.^[20] The gibbons split from the rest about 18 mya, and the hominid splits happened 14 mya (Pongo), 7 mya (Gorilla), and 3-5 mya (Homo & Pan).^{[citation needed]}

The families, genera and extant species of hominoids are:

• Superfamily Hominoidea^[1]
  • Family Hylobatidae: gibbons ("lesser apes")
    • Genus Hylobates
      • Lar gibbon or white-handed gibbon, H. lar
      • Bornean white-bearded gibbon, H. albibarbis
      • Agile gibbon or black-handed gibbon, H. agilis
      • Müller's Bornean gibbon or grey gibbon, H. muelleri
      • Silvery gibbon, H. moloch
      • Pileated gibbon or capped gibbon, H. pileatus
      • Kloss's gibbon or Mentawai gibbon or bilou, H. klossii
    • Genus Hoolock
      • Western hoolock gibbon, H. hoolock
      • Eastern hoolock gibbon, H. leuconedys
    • Genus Symphalangus
      • Siamang, S. syndactylus
    • Genus Nomascus
      • Black crested gibbon, N. concolor
      • Eastern black crested gibbon, N. nasutus
      • Hainan black crested gibbon, N. hainanus
      • Southern white-cheeked gibbon N. siki
      • White-cheeked crested gibbon, N. leucogenys
      • Yellow-cheeked gibbon, N. gabriellae
  • Family Hominidae: hominids ("great apes", including humans)
    • Genus Pongo: orangutans
      • Bornean orangutan, P. pygmaeus
      • Sumatran orangutan, P. abelii
    • Genus Gorilla: gorillas
      • Western gorilla, G. gorilla
      • Eastern gorilla, G. beringei
    • Genus Homo: humans
      • Human, H. sapiens
    • Genus Pan: chimpanzees
      • Common chimpanzee, P. troglodytes
      • Bonobo, P. paniscus

Cultural aspects of apes[link]

This unreferenced section requires citations to ensure verifiability.

Often, "apes" (nonhuman hominoids) are said to be the result of a curse—a Jewish folktale claims that one of the races who built the Tower of Babel became apes as punishment, while Muslim lore says that the Jews of Eilat became apes as punishment for fishing on the Sabbath. Some sects of Christianity have folklore that claims that these apes are a symbol of lust and were created by Satan in response to God's creation of humans.^{[citation needed]} It is uncertain whether any of these references are to any specific apes. All of these concepts date from a period when neither the distinction between apes and monkeys, nor the fact that humans are closely related to chimpanzees, was widely understood, if understood at all.

See also[link]

Mammals portal

• Chimp Haven
• Declaration on Great Apes from the Great Ape Project
• Human
• List of human evolution fossils
• List of apes (for notable non-fictional apes)
• List of fictional apes

Notes and references[link]

External links[link]

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Wikispecies has information related to: Ape

The Wikibook Dichotomous Key has a page on the topic of Hominoidea

• Pilbeam D (September 2000). "Hominoid systematics: The soft evidence". Proc. Natl. Acad. Sci. U.S.A. 97 (20): 10684–6. DOI:10.1073/pnas.210390497. PMC 34045. PMID 10995486. http://www.pnas.org/cgi/pmidlookup?view=long&pmid=10995486.  Agreement between cladograms based on molecular and anatomical data.

v t e Ape-related articles Ape species Human Bonobo Common chimpanzee Gorilla Orangutan Gibbon Ape study Ape language Great Ape Trust Dian Fossey Birutė Galdikas Jane Goodall Chimpanzee genome project Human genome project Neanderthal genome project Willie Smits Lone Drøscher Nielsen Borneo Orangutan Survival Legal and social status Personhood Research ban Kinshasa Declaration Great Ape Project Survival Project See also List of apes (non-human) Bushmeat Ape extinction List of fictional primates Human evolution Mythic humanoids Hominid

Sara Gruen is an author with dual citizen Canadian and American. Her books deal greatly with animals and she is a supporter of numerous charitable organizations that support animals and wildlife.^[1]

Early life and education[link]

Gruen was born in Vancouver, British Columbia. She grew up in London, Ontario, and attended the University of Ottawa in Ottawa,^[1][2] to get a degree in English Literature, where she continued to live for 10 years after her graduation.^[1]

Writing career[link]

Gruen moved to the United States from Ottawa in 1999 in order to take a technical writing job.^[3] When she was laid off two years later, she decided to try writing fiction. Gruen is an animal lover; both her first novel, Riding Lessons, and her second novel, Flying Changes, involve horses. Gruen's third book, the 1930s circus drama Water for Elephants, was initially turned down by her publisher at the time, Avon Books, forcing Gruen to find another publisher.^[4] It went on to become a New York Times bestseller and is now available in 44 languages and as a 2011 film adaptation starring Reese Witherspoon, Christoph Waltz, and Robert Pattinson.^[3] Her fourth novel, Ape House, centers around the Bonobo ape^[3] and was sold to Spiegel & Grau on the basis of a 12-page summary.^[4] Water for Elephants and Ape House are published by Two Roads Books.

Gruen’s awards include the 2007 Book Sense Book of the Year Award, the Cosmo Fun Fearless Fiction Award, the Bookbrowse Diamond Award for Most Popular Book, the Friends of American Literature Adult Fiction Award and the ALA/Alex Award 2007.^[3]

Personal life[link]

Gruen lives in North Carolina, with her husband, three sons, and seven animals.^[5]

References[link]

External links[link]

• Sara Gruen's Official Site