生物谷报道：对于人类而言，南极洲大部分的深海水域都还是一片“处女地”。不过，德国科学家通过近几年对南极附近的威德尔海（Weddell Sea，南极洲的边缘海）的3次探测，最终发现了从单细胞有孔微生物（foraminifera）到形状奇特的蟹类等700余种新的生物。新的发现不仅加深了科学家对于海洋生物进化的理解，而且有望打破之前关于极地生物多样性的认识。5月17日的《自然》杂志以封面文章的形式报道了这些发现和研究成果。
领导此次研究的德国汉堡大学动物学家Angelika Brandt表示，“我们在广阔、黑暗的深海中发现了数百种新的海洋生物。生活在威德尔海的食肉海绵、自由游动的蠕虫、甲壳类以及软体动物加深了人类对于海洋生物进化以及它们如何适应气候和环境变化的理解。”
2002年到2005年期间，作为“南极深海底栖生物多样性计划”（Antarctic benthic deep-sea biodiversity，简称ANDEEP）的一部分，德国“极地号”（Polarstern）考察船对于威德尔海域进行了3次探测研究。研究人员通过摄像机“捕获”了这些生活在数千米深的南极海底世界的神奇生物。
新发现的大量物种对黑暗深海中物种的进化和传播研究意义重大。比如，一种在威德尔海1000米深处发现的有孔微生物Epistominella vitrea在相对较浅的麦克默多海峡（McMurdo Sound）水域也大量存在，这表明该物种很可能是经过很长时间的冰河运动，由浅水区逐渐移居到深海的。同时，一些相对较大的甲壳类生物还保留着眼睛，这显然是一种进化的轨迹。
此外，科学家通过研究发现，一些有孔虫类甚至与北冰洋的类似生物具有相同的遗传基因，这很可能意味着这些微小生物是“世界大同，四海一家”（cosmopolitanism），分布在全球任何可能的海域。不过，对极地附近纬度水域的相关研究表明，绝大多数最新发现的南极深海生物还是独一无二的。
此次的发现有可能推翻科学家之前关于极地生物多样性的认识，即极地深海区域的生物多样性会减少。Brandt表示，“南极深海可能是地球海洋生物的‘摇篮’，它丰富的生物多样性令我们震惊，人类对极地深海确实还知之甚少。”
原始出处：
Nature 447, 307-311 (17 May 2007) | doi:10.1038/nature05827; Received 13 September 2006; Accepted 10 April 2007
First insights into the biodiversity and biogeography of the Southern Ocean deep sea
Angelika Brandt1, Andrew J. Gooday2, Simone N. Brandão1, Saskia Brix1, Wiebke Brökeland1, Tomas Cedhagen3, Madhumita Choudhury1, Nils Cornelius2, Bruno Danis4, Ilse De Mesel5, Robert J. Diaz6, David C. Gillan7, Brigitte Ebbe8, John A. Howe9, Dorte Janussen10, Stefanie Kaiser1, Katrin Linse11, Marina Malyutina12, Jan Pawlowski13, Michael Raupach14 & Ann Vanreusel5
Zoological Museum Hamburg, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany
National Oceanography Centre, Southampton, European Way, Southampton SO14 3ZH, UK
Department of Marine Ecology, University of Åarhus, Finlandsgade 14, 8200 Århus N, Denmark
Royal Belgian Institute of Natural Sciences, 29 Rue Vautier, 1000 Brussels, Belgium
Biology Department, Marine Biology Section, Ghent University, Krijgslaan 281/S8, 9000 Ghent, Belgium
Virginia Institute of Marine Science, College of William and Mary, Gloucester Point, Virginia 23062, USA
Marine Biology Laboratory, CP160/15, Université Libre de Bruxelles, 50 Avenue Roosevelt, 1050 Brussels, Belgium
Forschungsinstitut Senckenberg, DZMB-CeDAMar, c/o Forschungsmuseum König, Adenauerallee 160, 53113 Bonn, Germany
Scottish Association for Marine Science, Dunstaffnage Marine Laboratory, Dunbeg, Oban, Argyll PA37 1QA, UK
Forschungs und Naturmuseum Senckenberg, Senckenberganlage 25, 60325 Frankfurt am Main, Germany
British Antarctic Survey, Natural Environmental Research Council, High Cross, Madingley Road, Cambridge CB3 0ET, UK
Institute of Marine Biology, FEB RAS, Palchevskogo, 17, 690041 Vladivostok, Russia
Department of Zoology & Animal Biology, University of Geneva, 30 Quai Ernest Ansermet, CH 1211 Genève 4, Switzerland
Ruhr-Universität Bochum, Universitätstrasse 150, 44780 Bochum, Germany
Correspondence to: Angelika Brandt1 Correspondence and requests for materials should be addressed to A.B. (Email: abrandt@zoologie.uni-hamburg.de).
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Shallow marine benthic communities around Antarctica show high levels of endemism, gigantism, slow growth, longevity and late maturity, as well as adaptive radiations that have generated considerable biodiversity in some taxa1. The deeper parts of the Southern Ocean exhibit some unique environmental features, including a very deep continental shelf2 and a weakly stratified water column, and are the source for much of the deep water in the world ocean. These features suggest that deep-sea faunas around the Antarctic may be related both to adjacent shelf communities and to those in other oceans. Unlike shallow-water Antarctic benthic communities, however, little is known about life in this vast deep-sea region2, 3. Here, we report new data from recent sampling expeditions in the deep Weddell Sea and adjacent areas (748–6,348 m water depth) that reveal high levels of new biodiversity; for example, 674 isopods species, of which 585 were new to science. Bathymetric and biogeographic trends varied between taxa. In groups such as the isopods and polychaetes, slope assemblages included species that have invaded from the shelf. In other taxa, the shelf and slope assemblages were more distinct. Abyssal faunas tended to have stronger links to other oceans, particularly the Atlantic, but mainly in taxa with good dispersal capabilities, such as the Foraminifera. The isopods, ostracods and nematodes, which are poor dispersers, include many species currently known only from the Southern Ocean. Our findings challenge suggestions that deep-sea diversity is depressed in the Southern Ocean and provide a basis for exploring the evolutionary significance of the varied biogeographic patterns observed in this remote environment.
