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''Ganlea'' is a fossil primate from central Myanmar, formerly known as Burma. Its age is about 38 million years, living during the late Eocene epoch. ''Ganlea'' belongs to the group of anthropoids (i. e. humans, apes and monkeys), and is in the family Amphipithecidae. It is older than any other known anthropoid from Africa, and is the second oldest known from Asia. Its remains consist of teeth and jawbones belonging to 10 to 15 individuals found near the city of Bagan in the central part of the country. The teeth of ''Ganlea'' have many diagnostic features that help to show its relations with other anthropoids. It is thought to be closely related to the genera ''Myanmarpithecus'', ''Pondaungia'' and ''Siamopithecus'', both found from the same area as ''Ganlea''. In all of these genera, the canine tooth is enlarged and compressed anteroposteriorly, making it quite wide. A great deal of tooth wear has been observed in ''Ganlea'', which has been viewed as an adaptation for consuming nuts and seeds, similar to the modern Saki monkey. The large size of the canine tooth in ''Ganlea'' gives it the specific name "''megacanina''". Phylogenetic analyses conducted upon the description of ''Ganlea'' suggest that the amphipithecids are closely related to New World monkeys (Platyrrhini) and the extinct propliopithecids. This places it firmly within Haplorrhini. ''Darwinius'', a primate recently described and quickly claimed a transitional fossil of great importance to human ancestry, is a member of the Adapiformes, which has recently been viewed as a transitional group between Strepsirrhini and Haplorrhini. This means that ''Ganlea'' is more closely related to modern monkeys and apes than ''Darwinius'' is. Because of its age, ''Ganlea'' has been called a missing link that places the origin of all anthropoids (including humans) in Asia rather than Africa as was previously thought. However, doubts have been raised towards the claim that it is the ancestor of all other anthropoids.〔(Ganlea on scienceblog.com, by Brian Switek )〕 Other extinct primates such as ''Eosimias'' seem to be more basal members than ''Ganlea''.〔The description of ''Eosimias'' by Beard ''et al.'' in 1994 can be seen as the beginning of the recent debate on the Asian ancestry of anthropoids〕 Because ''Ganlea'' is a true anthropoid, it has been seen as more likely to be a direct ancestor of monkeys and apes (and thus humans) than ''Darwinius'' would. However, the phylogenetic analysis that was conducted on it suggests that it is too derived to have been an ancestral anthropoid, and its close relation with New World monkeys seems to imply that it was not a human ancestor, as apes are believed to have evolved from Old World monkeys. == See also == * Anthrasimias * Biretia 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Ganlea」の詳細全文を読む スポンサード リンク
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