Primates A primate ( With the exception of humans, which inhabit every continent,[a] most primates live in tropical or subtropical regions of the Americas, Africa and Asia.[5] They range in size from Madame Berthe's mouse lemur, which weighs only 30 g (1 oz), to the eastern lowland gorilla, weighing over 200 kg (440 lb). Based on fossil evidence, the earliest known true primates, represented by the genus Teilhardina, date to 55.8 million years old.[6] An early close primate relative known from abundant remains is the Late Paleocene Plesiadapis, circa 55–58 million years old.[7] Molecular clock studies suggest that the primate branch may be even older, originating in the mid-Cretaceous period around 85 mya.[7] Considered generalist mammals, primates exhibit a wide range of characteristics. Some primates (including some great apes and baboons) are primarily terrestrial rather than arboreal, but all species possess adaptations for climbing trees. Historical and modern terminology[edit]
Hominini Through DNA comparison, scientists believe the Pan / Homo divergence occurred between 5.4 and 6.3 million years ago, after an unusual process of speciation that ranged over 4 million years.[5] Few fossil specimens on the Pan side of the split have been found, the first fossil chimpanzee discovery being published in 2005,[6] dating to between 545 ± 3 kyr (thousand years) and 284 ± 12 kyr via Argon-argon dating, from Kenya's East African Rift Valley. All of the extinct genera listed in the table to the right are ancestral to Homo, or are offshoots of such. However, both Orrorin and Sahelanthropus existed around the time of the split, and so may be ancestral to all three extant species. In the proposal of Mann and Weiss (1996),[7] the tribe Hominini includes Pan as well as Homo, but within separate subtribes. Homo (and, by inference, all bipedal apes) is in the subtribe Hominina, while Pan is in the subtribe Panina. Wood (2010) discusses the different views of this taxonomy.[8]
Homo Homo is the genus of hominids that includes modern humans and species closely related to them. The genus is estimated to be about 2.3 to 2.4 million years old,[1][2] possibly having evolved from australopithecine ancestors, with the appearance of Homo habilis. Several species, including Australopithecus garhi, Australopithecus sediba, Australopithecus africanus, and Australopithecus afarensis, have been proposed as the direct ancestor of the Homo lineage.[3][4] These species have morphological features that align them with Homo, but there is no consensus on which gave rise to Homo, assuming it was not an as-yet undiscovered species. The most salient physiological development between the earlier australopith species and Homo is the increase in cranial capacity, from about 450 cm3 (27 cu in) in A. garhi to 600 cm3 (37 cu in) in H. habilis. Homo sapiens (modern humans) is the only surviving species in the genus, all others having become extinct. Naming[edit] Species[edit] See also[edit]
Human Humans began to practice sedentary agriculture about 12,000 years ago, domesticating plants and animals which allowed for the growth of civilization. Humans subsequently established various forms of government, religion, and culture around the world, unifying people within a region and leading to the development of states and empires. The rapid advancement of scientific and medical understanding in the 19th and 20th centuries led to the development of fuel-driven technologies and improved health, causing the human population to rise exponentially. By 2012 the global human population was estimated to be around 7 billion.[10][11] Etymology and definition In common usage, the word "human" generally refers to the only extant species of the genus Homo — anatomically and behaviorally modern Homo sapiens. In scientific terms, the definition of "human" has changed with the discovery and study of the fossil ancestors of modern humans. History Evolution and range Evidence from molecular biology
Pan paniscus (Bonobo) The bonobo (/bəˈnoʊboʊ/ or /ˈbɒnəboʊ/), Pan paniscus, formerly called the pygmy chimpanzee and less often, the dwarf or gracile chimpanzee,[3] is a great ape and one of the two species making up the genus Pan; the other is Pan troglodytes, or the common chimpanzee. Although the name "chimpanzee" is sometimes used to refer to both species together, it is usually understood as referring to the common chimpanzee, while Pan paniscus is usually referred to as the bonobo. It is distinguished by relatively long legs, pink lips, dark face and tail-tuft through adulthood, and parted long hair on its head. The bonobo is popularly known for its high levels of sexual behavior. Along with the common chimpanzee, the bonobo is the closest extant relative to humans. Etymology[edit] Despite the alternative common name "pygmy chimpanzee", the bonobo is not especially diminutive when compared to the common chimpanzee. Evolutionary history[edit] Fossils[edit] Taxonomy and phylogeny[edit] Female bonobo
Pan Troglodytes (Common chimpanzee) The common chimpanzee (Pan troglodytes), also known as the robust chimpanzee, is a species of great ape. Colloquially, the common chimpanzee is often called the chimpanzee (or "chimp"), though this term can be used to refer to both species in the genus Pan: the common chimpanzee and the closely related bonobo, formerly called the pygmy chimpanzee. Evidence from fossils and DNA sequencing show both species of chimpanzees are the sister group to the modern human lineage. The common chimpanzee lives in groups which range in size from 15 to 150 members, although individuals travel and forage in much smaller groups during the day. The common chimpanzee is listed on the IUCN Red List as an endangered species. Etymology[edit] The English name chimpanzee came from a Bantu language of Angola.[7] Evolutionary history[edit] Despite a large number of Homo fossil finds, chimpanzee fossils (genus Pan) were not described until 2005. Taxonomy[edit] Physical description[edit] Ecology[edit] Behavior[edit]
Pan (Chimpanzee) Chimpanzees, sometimes colloquially chimp, are two extant hominid species of apes in the genus Pan. The Congo River divides the native habitats of the two species:[2] Chimpanzees are members of the family Hominidae, along with gorillas, humans, and orangutans. Evolutionary history Evolutionary relationship Fossils Though many human fossils have been found, chimpanzee fossils were not described until 2005. Anatomy and physiology Human and chimp skulls and brains (not to scale), as illustrated in Gervais' Histoire naturelle des mammifères The male common chimp stands up to 1.7 m (5.6 ft) high and weighs as much as 70 kg (150 lb); the female is somewhat smaller. Both the common chimpanzee and bonobo can walk upright on two legs when carrying objects with their hands and arms. Chimpanzee testicles are unusually large for their body size, with a combined weight of about 4 oz (110 g) compared to a gorilla's 1 oz (28 g) or a human's 1.5 ounces (43 g). Neoteny Behavior Bonobo Social structure Tool use
Gorilla Gorillas constitute the eponymous genus Gorilla, the largest extant genus of primates by physical size. They are ground-dwelling, predominantly herbivorous apes that inhabit the forests of central Africa. The genus is divided into two species and either four or five subspecies. The DNA of gorillas is highly similar to that of a human, from 95–99% depending on what is counted, and they are the next closest living relatives to humans after the chimpanzees (including bonobos). Gorillas' natural habitats cover tropical or subtropical forests in Africa. Etymology Evolution and classification Primatologists continue to explore the relationships between various gorilla populations.[8] The species and subspecies listed here are the ones upon which most scientists agree. The proposed third subspecies of Gorilla beringei, which has not yet received a trinomen, is the Bwindi population of the mountain gorilla, sometimes called the Bwindi gorilla. Physical characteristics A skull of a gorilla Nesting
Homo sapiens idaltu Homo sapiens idaltu is an extinct subspecies of Homo sapiens that lived almost 160,000 years ago in Pleistocene Africa.[1] "Idaltu" is from the Saho-Afar word meaning "elder" or "first born".[1] Discovery[edit] The fossilized remains of H. s. idaltu were discovered at Herto Bouri near the Middle Awash site of Ethiopia's Afar Triangle in 1997 by Tim White, but were first unveiled in 2003.[1] Herto Bouri is a region of Ethiopia under volcanic layers. By using radioisotope dating, the layers date between 154,000 and 160,000 years old. Morphology and taxonomy[edit] Despite the archaic features, these specimens were argued to represent the direct ancestors of modern Homo sapiens sapiens which, according to the "recent African origin (RAO)" or "out of Africa" model, developed shortly after this period (Khoisan mitochondrial divergence dated not later than 110,000 BCE) in Eastern Africa. An exact description was made, by its discoverers, of H. s. idaltu:[1] Location of discovery See also[edit]