Debruyne Régis
Muséum National d'Histoire Naturelle, Département Histoire de la Terre, UMR 5143, CNRS, Paleobiodiversite, 57, rue Cuvier, 75231 Paris.
J Soc Biol. 2004;198(4):335-42.
African elephants are conventionally classified as a single species: Loxodonta africana (Blumenbach 1797). However, the discovery in 1900 of a smaller form of the African elephant, spread throughout the equatorial belt of this land, has given rise to a debate over the relevance of a second species of elephant in Africa. The twentieth century has not provided any definite answer to this question. Actually, recent molecular analyses have sustained this issue by advocating either a division of forest elephants into a valid species, or their inclusion as a subspecies of L. africana. Our work initiated at the National Museum of Natural History of Paris provides new molecular (mitochondrial) and morphological (and morphometrical) evidence making it possible to propose a comprehensive phylogenetic hypothesis. It appears that there is no conclusive argument to keep forest elephants (cyclotis form) and savannah elephants (africana form) apart in two distinct species. A high level of mitochondrial introgression between the two forms, as well as a continuum in the morphology of the skulls of the two morphotypes rather suggests that, despite an ancient division, these two taxa freely interbreed wherever their ranges intersect. We thus adopt a conservative systematic position in considering these two forms as two subspecies, respectively: L. africana africana, the savannah elephant, and L. africana cyclotis, the forest elephant. We finally discuss the conservation topic in the light of this systematic framework.
非洲象（Loxodonta africana，布卢门巴赫，1797年）。然而，1900年发现了一种体型较小的非洲象，分布在这片土地的赤道带，这引发了一场关于非洲是否存在第二种象的相关性的争论。二十世纪尚未对这个问题给出任何明确答案。实际上，最近的分子分析通过主张将森林象划分为一个有效物种，或者将它们归入非洲象的一个亚种，使这个问题持续存在。我们在巴黎国家自然历史博物馆开展的工作提供了新的分子（线粒体）和形态学（及形态测量学）证据，从而有可能提出一个全面的系统发育假说。似乎没有确凿的论据将森林象（圆耳象形态）和草原象（非洲象形态）分在两个不同的物种中。两种形态之间线粒体的高度渐渗，以及两种形态类型头骨形态的连续性，反而表明，尽管它们在远古时期就已分化，但这两个分类单元在其分布范围相交的任何地方都能自由杂交。因此，我们采取保守的分类学立场，将这两种形态分别视为两个亚种：草原象，即非洲象指名亚种（L. africana africana），以及森林象，即非洲象圆耳亚种（L. africana cyclotis）。我们最后根据这个分类框架讨论了保护问题。
