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''Darwinius'' is a genus within the infraorder Adapiformes, a group of basal strepsirrhine primates from the middle Eocene epoch. Its only known species, ''Darwinius masillae'', lived approximately 47 million years ago (Lutetian stage) based on dating of the fossil site.〔Mertz, D.F., Renne, P.R. (2005): A numerical age for the Messel fossil deposit (UNESCO World Heritage Site) derived from 40Ar/39Ar dating on a basaltic rock fragment. ''Courier Forschungsinstitut Senckenberg'' no 255: pp 7–75.〕 The only known fossil, called Ida, was discovered in 1983 at the Messel pit, a disused quarry near the village of Messel, (Landkreis Darmstadt-Dieburg, Hesse) about 35 km (22 mi) southeast of Frankfurt am Main, Germany. The fossil, divided into a slab and partial counterslab after the amateur excavation and sold separately, was not reassembled until 2007. The fossil is of a juvenile female, approximately overall length, with the head and body length excluding the tail being about . It is estimated that Ida died at about 80–85% of her projected adult body and limb length.〔 The genus ''Darwinius'' was named in commemoration of the bicentenary of the birth of Charles Darwin, and the species name ''masillae'' honors Messel where the specimen was found. The creature appeared superficially similar to a modern lemur.〔〔 The authors of the paper describing ''Darwinius'' classified it as a member of the primate family Notharctidae, subfamily Cercamoniinae,〔 suggesting that it has the status of a significant transitional form (a "link") between the prosimian and simian ("anthropoid") primate lineages. Others have disagreed with this placement.〔(Fossil primate challenges Ida's place ) Nature 461, 1040 (2009)〕〔(【引用サイトリンク】title=‘Missing link’ primate isn’t a link after all )〕 Concerns have been raised about the claims made about the fossil's relative importance and the publicising of the fossil before adequate information was available for scrutiny by the academic community.〔 Some of Norway's leading biologists, among them Nils Christian Stenseth, have called the fossil an "exaggerated hoax" and stated that its presentation and popular dissemination "fundamentally violate scientific principles and ethics."〔Amundsen, Trond; Folstad, Ivar; Giske, Jarl; Slagsvold, Tore; Stenseth, Nils Chr. ('Ida' er oversolgt ), ''Aftenposten''〕〔(– Ida er en oversolgt bløff ), ''Nettavisen''〕〔(– Dette er ingen 'missing link' ), ''Dagbladet'', 20 May 2009〕 ==Taxonomy== Franzen et al. (2009) place the genus ''Darwinius'' in the subfamily Cercamoniinae of the family Notharctidae within the extinct suborder Adapiformes of early primates.〔 ''Darwinius masillae'' is the third primate species to be discovered at the Messel locality that belongs to the cercamoniine adapiforms, in addition to ''Europolemur koenigswaldi'' and ''Europolemur kelleri''. ''Darwinius masillae'' is similar but not directly related to ''Godinotia neglecta'' from Geiseltal. The adapiforms are early primates which are known only from the fossil record, and it is unclear whether they form a suborder proper or a paraphyletic grouping. They are usually grouped under Strepsirrhini—including lemurs, aye-ayes and lorisoids—and as such would not be ancestral to Haplorrhini, which includes tarsiers and simians.〔Callum Ross, Richard F. Kay, ''Anthropoid origins: new visions'', Springer, 2004, ISBN 978-0-306-48120-8, p. 100〕 Simians are usually called "anthropoid": while this term can be confusing, the paper uses it, as does associated publicity material. Simians (anthropoids) include monkeys and apes, which in turn includes humans. Franzen et al. in their 2009 paper place ''Darwinius'' in the "Adapoidea group of early primates representative of early haplorhine diversification". This means that, according to these authors, the adapiforms would not be entirely within the Strepsirrhini lineage as hitherto assumed, but would qualify as a transitional fossil (a "missing link") between Strepsirrhini and Haplorrhini, and so could be ancestral to humans. They also suggest that tarsiers have been misplaced in the Haplorrhini and should be considered Strepsirrhini. To support this view they show that as many as six morphological traits found in "Darwinius" are derived characters present only in the Haplorrhini lineage, but absent in the Strepsirrhini lineage, which they interpret as synapomorphies. These include, among others, a cranium with a short rostrum, deep mandibular ramus, loss of all grooming claws. They note "that ''Darwinius masillae'' and adapoids contemporary with early tarsioids could represent a stem group from which later anthropoid primates evolved, but we are not advocating this here, nor do we consider either ''Darwinius'' or adapoids to be anthropoids."〔 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「Darwinius」の詳細全文を読む スポンサード リンク
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