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Baobab is the common name for each of the nine species of tree in the genus ''Adansonia''. The generic name honours Michel Adanson, the French naturalist and explorer who described ''Adansonia digitata''. Of the nine species, six are native to Madagascar, two are native to mainland Africa and the Arabian Peninsula, and one is native to Australia. One of the mainland African species also occurs on Madagascar, but it is not a native of that island. It was introduced in ancient times to south Asia and during the colonial era to the Caribbean. It is also present in the island of Cape Verde. The ninth species was described in 2012, and is found in upland populations of southern and eastern Africa. The African and Australian baobabs are almost identical, having separated less than 100,000 years ago.〔''Baum D. A.'', ''Small R. L.'', ''Wendel J. F.'' Biogeography and floral evolution of baobabs (Adansonia, Bombacaceae) as inferred from multiple data sets. Syst Biol 1998; 47:181–207.〕 Adansonias reach heights of and have trunk diameters of . The Glencoe baobab, a specimen of ''A. digitata'' in Limpopo Province, South Africa, was considered to be the largest living individual, with a maximum circumference of and a diameter of about . The tree has since split into two parts, so the widest individual trunk may now be that of the Sunland baobab, or Platland tree, also in South Africa. The diameter of this tree at ground level is and its circumference at breast height is .〔Patrut, A., et al. (2010). (Fire history of a giant African baobab evinced by radiocarbon dating. ) ''Radiocarbon'' 52(2), 717-26.〕 ''Adansonia'' trees produce faint growth rings, probably annually, but they are not reliable for aging specimens, because they are difficult to count and may fade away as the wood ages. Radiocarbon dating has provided data on a few individuals. A specimen of ''A. digitata'' known as Grootboom was dated and found to be at least 1275 years old, making it one of the oldest known angiosperm trees.〔〔(【引用サイトリンク】title=''Adansonia digitata'' (baobab) )〕 ==Habitat== The Malagasy species are important components of the Madagascar dry deciduous forests. Within that biome, ''Adansonia madagascariensis'' and ''A. rubrostipa'' occur specifically in the Anjajavy Forest, sometimes growing out of the tsingy limestone itself. ''A. digitata'' has been called "a defining icon of African bushland".〔 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「Adansonia」の詳細全文を読む スポンサード リンク
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