Gibbons and orang-utans swing under-arm from branch to branch by their very long fore arms gibbons also walk upright on their hind limbs. LOCOMOTION AND MANUAL DEXTERITY OF APES AND HUMANSĭifferent ape species move in different ways. The human canine tooth is not as good a weapon. Apes have greatly developed canines with sharp blades, which hone against the modified shearing edge of the first lower premolar tooth, and may be used as weapons. Used together, these teeth enable most apes and humans to process a variety of vegetarian food stuffs. The presence of squared off cheek teeth reflects the predominance of plant food in the diet. The molars have 5 cusps and a complex arrangement of ridges on their grinding surfaces. The teeth include spatulate (shovel-shaped) incisors and prominent canines the rear edge of the upper canine hones against the front edge of the first lower premolars. The dental formula is the same as Old World Monkeys: I2/2 C1/1 P2/2 M3/3 = 32. DENTITIONĪpes have relatively well developed jaws: the lower jaw is fairly deep and the two halves are fused in the front. The skull of the chimpanzee (4) is very like a human skull. The human cranium (5) is smooth-domed and lacks crests the brain cavity is very large. The skulls of male gorillas (3) and orang utans are much more heavily built than the females and also have substantial midline (sagittal) and neck (nuchal) crests to provide additional attachment surfaces for neck muscles. Orang utan skulls (2) slope markedly backwards, unlike the skulls of gorillas (3) and chimpanzees (4). The skulls of the heavier great apes and humans (2-5) are robust to protect the brain from damage. Gibbon skulls (1) are relatively light and there is little difference in the skulls of males and females, they have the largest canines, relatively speaking, of all apes. Skulls of Homo sapiens, a human being one skull prepared to show brain case. Skull of Pan troglodytes, the common chimpanzee, from West and Central Africa.ĥ. Skulls of male and female Gorilla gorilla, the Western gorilla, from Equatorial Africa.Ĥ. Skull of Pongo pygmaeus, the Bornean orang-utan.ģ. Skull of Hylobates hoolock, white-browed or hoolock gibbon, from South East Asia – Bangladesh, Burma, Assam.Ģ. Thomson, copyright The Royal Zoological Society ofġ. This arrangement allows the eyes to face forward when the body is upright.Ĭourtesy of Alan R. The foramen magnum, the opening in the base of the cranium where the spinal cord goes into the vertebral column, is ventrally placed underneath the skull. The frontal bones are fused at the midline. The characteristic appearance of the heads and faces of the different apes and humans reflects the different shapes of their skulls.Īpes' skulls have flattened faces with complete and forward pointing bony sockets for the eye – a plate of bone separates the orbit from the jaw muscle. All apes lack tails as they are not needed for balancing. The two bones (ulna and radius) in the lower fore limb and the two bones (tibia and fibula) in lower hind limb of apes are separate and highly mobile. Apes have extremely flexible shoulders, elbows and wrists. Apes’ fore limbs are longer than their hind limbs (except for humans). The development of a vertical posture in apes was accompanied by increased manual dexterity. These features are related to the upright posture of their bodies. The length of spine between rib cage and pelvis is much shorter in apes than in monkeys. While apes occur only in tropical or subtropical regions of the Old World, namely Africa and Asia, humans live in all regions of the world.Īs so much information about apes and humans is readily and easily available from other sources, including the World Wide Web, this page on apes has been planned only to illustrate our ape skulls and skeletons so they can be compared to the skulls and skeletons of the other animals in our Collections.Īs the skeleton of a chimpanzee (1) and gibbon (2) to the right show, apes have short backs with wide, barrel-shaped chests and robust pelvic girdles. This website follows the scheme whereby modern humans, Homo sapiens, are assigned to the family Hominidae with the apes. The apes are humans’ closest relatives but the place of humans in the classification schemes of apes is controversial. The family Hominidae comprises the great apes - orang utans, chimpanzees, bonobos, gorillas.The family Hylobatidae comprises the lesser apes - gibbons and siamangs, which are highly adapted to an arboreal existence.Within the infraorder Catarrhini, apes and humans are assigned to two families in the superfamily Hominoidea. The name catarrhine literally means ‘drooping nose’. SUBORDER HAPLORHINI INFRAORDER CATARRHINI SUPERFAMILY HOMINOIDEA APES AND HUMANSĪpes are grouped together with Old World monkeys in the infra-order Catarrhini because their nostrils are narrow and close together.
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