|
Sahelanthropus Tchadensis
''Sahelanthropus'' is an extinct genus of hominid dated to about during the Late Miocene. The type species, ''Sahelanthropus tchadensis'', was first announced in 2002, based mainly on a partial cranium, nicknamed ''Toumaï'', discovered in northern Chad. The definitive phylogenetic position of ''Sahelanthropus'' within hominids is uncertain. It was initially described as a possible hominin ancestral to both humans and chimpanzees, but subsequent interpretations suggest that it could be an early member of the tribe Gorillini or a stem-hominid outside the hominins. Examinations on the postcranial skeleton of ''Sahelanthropus'' also indicated that this taxon was not a habitual biped. Taxonomy Discovery Four employees of the Centre National d'Appui à la Recherche (CNAR, National Research Support Center) of the Ministry of Higher Education of the Republic of Chad, three Chadians (Ahounta Djimdoumalbaye, Fanoné Gongdibé and Mahamat Adoum) and one French (Alain Beauvilain) collecte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Messinian
The Messinian is in the geologic timescale the last age or uppermost stage of the Miocene. It spans the time between 7.246 ± 0.005 Ma and 5.333 ± 0.005 Ma (million years ago). It follows the Tortonian and is followed by the Zanclean, the first age of the Pliocene. The Messinian overlaps the Turolian European Land Mammal Mega Zone (more precisely MN 12 and 13) and the Pontian Central European Paratethys Stage. It also overlaps the late Huayquerian and early Montehermosan South American Land Mammal Ages, and falls inside the more extensive Hemphillian North American Land Mammal Age. During the Messinian, around 6 million years ago, the Messinian salinity crisis took place, which brought about repeated desiccations of the Mediterranean Sea. Definition The Messinian was introduced by Swiss stratigrapher Karl Mayer-Eymar in 1867. Its name comes from the Italian city of Messina on Sicily, where the Messinian evaporite deposit is of the same age. The base of the Messinian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incisor
Incisors (from Latin ''incidere'', "to cut") are the front teeth present in most mammals. They are located in the premaxilla above and on the mandible below. Humans have a total of eight (two on each side, top and bottom). Opossums have 18, whereas armadillos, anteaters and other animals in the order Edentata have none. Structure Adult humans normally have eight incisors, two of each type. The types of incisors are: * maxillary central incisor (upper jaw, closest to the center of the lips) * maxillary lateral incisor (upper jaw, beside the maxillary central incisor) * mandibular central incisor (lower jaw, closest to the center of the lips) * mandibular lateral incisor (lower jaw, beside the mandibular central incisor) Children with a full set of deciduous teeth (primary teeth) also have eight incisors, named the same way as in permanent teeth. Young children may have from zero to eight incisors depending on the stage of their tooth eruption and tooth development. Typic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hissène Habré
Hissène Habré (Arabic: ''Ḥusaīn Ḥabrī'', Chadian Arabic: ; ; 13 August 1942 – 24 August 2021), also spelled Hissen Habré, was a Chadian politician and convicted war criminal who served as the 5th president of Chad from 1982 until he was deposed in 1990. A Muslim from northern Chad, Habré joined FROLINAT rebels in the first Chadian Civil War against the southern-dominated Chadian government. Due to a rift with fellow rebel commander Goukouni Oueddei, Habré and his Armed Forces of the North rebel army briefly defected to Felix Malloum's government against Oueddei before turning against Malloum, who resigned in 1979. Habré was then given the position of Minister of Defense under Chad's new transitional coalition government, with Oueddei as President. Their alliance quickly collapsed, and Habré's forces overthrew Oueddei in 1982. Having become the country's new president, Habré created the National Union for Independence and Revolution (UNIR) as the cou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Daza Language
Daza (also known as Dazaga) is a Nilo-Saharan language spoken by the Daza people (a sub-group of the Toubou people) inhabiting northern Chad and eastern Niger. The Daza are also known as the Gouran (Gorane) in Chad. Dazaga is spoken by around 700,000 people, primarily in the Djurab Desert region and the Borkou region, locally called Haya or Faya-Largeau northern-central Chad, in Kanem there is a lot of Daza around 300,000, the capital of the Dazaga people. Dazaga is spoken in the Tibesti Mountains of Chad (606,000 speakers), in eastern Niger near N'guigmi and to the north (93,200 speakers). It is also spoken to a smaller extent in Libya and in Sudan, where there is a community of 3,000 speakers in the city of Omdurman. There's also a small diaspora community working in Jeddah, Saudi Arabia. The two primary dialects of the Dazaga language are Daza and Kara, but there are several other mutually intelligible dialects, including Kaga, Kanobo, Taruge and Azza. It is closely related ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Idriss Déby
Idriss Déby Itno ( '; 18 June 1952 – 20 April 2021) was a Chadian politician and military officer who was the sixth List of heads of state of Chad, president of Chad from 1991 until his death in 2021 during the 2021 Northern Chad offensive, Northern Chad offensive. His term of office of more than 30 years makes him Chad's longest-serving president. Déby was a member of the Bidayat dialect, Bidayat clan of the Zaghawa people, Zaghawa ethnic group. A high-ranking commander of President Hissène Habré's military during the 1980s, Déby played important roles in the Toyota War which led to Chad's victory during the Chadian–Libyan War, Chadian-Libyan War. He was later purged by Habré after being suspected of plotting a coup, and was forced into exile in Libya. He took power by leading a 1990 Chadian coup d'état, coup d'état against Habré in December 1990. Despite introducing a multi-party system in 1992 after several decades of one-party rule under his predecessors, througho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homo
''Homo'' () is a genus of great ape (family Hominidae) that emerged from the genus ''Australopithecus'' and encompasses only a single extant species, ''Homo sapiens'' (modern humans), along with a number of extinct species (collectively called archaic humans) classified as either ancestral or closely related to modern humans; these include ''Homo erectus'' and ''Homo neanderthalensis''. The oldest member of the genus is ''Homo habilis'', with records of just over 2 million years ago. ''Homo'', together with the genus ''Paranthropus'', is probably most closely related to the species ''Australopithecus africanus'' within ''Australopithecus''.'''' The closest living relatives of ''Homo'' are of the genus ''Pan (genus), Pan'' (chimpanzees and bonobos), with the ancestors of ''Pan'' and ''Homo'' estimated to have diverged around 5.7–11 million years ago during the Late Miocene. ''H. erectus'' appeared about 2 million years ago and spread throughout Africa (deba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great Ape
The Hominidae (), whose members are known as the great apes or hominids (), are a taxonomic family of primates that includes eight extant species in four genera: '' Pongo'' (the Bornean, Sumatran and Tapanuli orangutan); '' Gorilla'' (the eastern and western gorilla); '' Pan'' (the chimpanzee and the bonobo); and ''Homo'', of which only modern humans (''Homo sapiens'') remain. Numerous revisions in classifying the great apes have caused the use of the term ''hominid'' to change over time. The original meaning of "hominid" referred only to humans (''Homo'') and their closest extinct relatives. However, by the 1990s humans and other apes were considered to be "hominids". The earlier restrictive meaning has now been largely assumed by the term ''hominin'', which comprises all members of the human clade after the split from the chimpanzees (''Pan''). The current meaning of "hominid" includes all the great apes including humans. Usage still varies, however, and some scientis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australopithecus Bahrelghazali
''Australopithecus bahrelghazali'' is an extinct species of australopithecine discovered in 1995 at Koro Toro, Bahr el Gazel, Chad, existing around 3.5 million years ago in the Pliocene. It is the first and only australopithecine known from Central Africa, and demonstrates that this group was widely distributed across Africa as opposed to being restricted to East and southern Africa as previously thought. The validity of ''A. bahrelghazali'' has not been widely accepted, in favour of classifying the specimens as '' A. afarensis'', a better known Pliocene australopithecine from East Africa, because of the anatomical similarity and the fact that ''A. bahrelghazali'' is known only from 3 partial jawbones and an isolated premolar. The specimens inhabited a lakeside grassland environment with sparse tree cover, possibly similar to the modern Okavango Delta, and similarly predominantly ate C4 savanna foods—such as grasses, sedges, storage organs, or rhizomes—and to a lesser deg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sahel
The Sahel region (; ), or Sahelian acacia savanna, is a Biogeography, biogeographical region in Africa. It is the Ecotone, transition zone between the more humid Sudanian savannas to its south and the drier Sahara to the north. The Sahel has a Semi-arid climate#Hot semi-arid climates, hot semi-arid climate and stretches across the tropics, southernmost latitudes of North Africa between the Atlantic Ocean and the Red Sea. Although geographically located in the tropics, the Sahel does not have a tropical climate. Especially in the western Sahel, there are droughts in the Sahel, frequent shortages of food and water due to its very high Corruption Perceptions Index, government corruption and the semi-arid climate. This is exacerbated by very high list of countries by birth rate, birthrates across the region, resulting in a rapid increase in population. In recent times, various Coup Belt, coups, Foreign internal defense#Preemptive counterinsurgency in Africa, insurgencies, terrorism ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. Other ways of defining species include their karyotype, DNA sequence, morphology (biology), morphology, behaviour, or ecological niche. In addition, palaeontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. About 14% of these had been described by 2011. All species (except viruses) are given a binomial nomenclature, two-part name, a "binomen". The first part of a binomen is the name of a genus to which the species belongs. The second part is called the specific name (zoology), specific name or the specific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants of an ancestral taxon are grouped together (i.e. Phylogeneti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holotype Specimen
A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was Species description, formally described. It is either the single such physical example (or illustration) or one of several examples, but explicitly designated as the holotype. Under the International Code of Zoological Nomenclature (ICZN), a holotype is one of several kinds of name-bearing types. In the International Code of Nomenclature for algae, fungi, and plants (ICN) and ICZN, the definitions of types are similar in intent but not identical in terminology or underlying concept. For example, the holotype for the butterfly ''Plebejus idas, Plebejus idas longinus'' is a preserved specimen of that subspecies, held by the Museum of Comparative Zoology at Harvard University. In botany and mycology, an isotype is a duplicate of the holotype, generally pieces from the same individual plant or samples from the same genetic individual. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
