Fautin Daphne Gail, Malarky Lacey, Soberón Jorge
Biodiversity Institute and Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS 66045, USA.
Biol Bull. 2013 Apr;224(2):89-98. doi: 10.1086/BBLv224n2p89.
We sought to determine if the global distribution of sea anemones (cnidarian order Actiniaria) conforms to the classic pattern of biogeography--taxon richness at the equator with attenuation toward the poles--a pattern that is derived almost entirely from data on terrestrial plants and animals. We plotted the empirical distribution of species occurrences in 10° bands of latitude based on published information, then, using the Chao2 statistic, inferred the completeness of that inventory. We found the greatest species richness of sea anemones at 30-40° N and S, with lower numbers at tropical latitudes and the fewest species in polar areas. The Chao2 statistic allowed us to infer that the richness pattern we found is not due to particularly poor knowledge of tropical sea anemones. No 10° band of latitude has less than 60% of the theoretical number of species known, but for only about half of them could we reject the null hypothesis (P = 0.05) that information is complete; anemone diversity is best documented at high latitudes. We infer that the 1089 valid species currently known constitute about 70% of the theoretical total of about 1500 species of Actiniaria. The distribution pattern of sea anemone species resembles that of planktonic foraminiferans and benthic marine algae, although planktonic bacteria, marine bivalves, and shallow and deep scleractinian corals show the terrestrial pattern of equatorial richness attenuating with latitude. Sea anemone species richness is complementary to that of scleractinian corals at many scales; our findings affirm it at the global scale.
我们试图确定海葵（刺胞动物门海葵目）的全球分布是否符合生物地理学的经典模式——赤道地区分类单元丰富度高，向两极递减，这种模式几乎完全来自陆地植物和动物的数据。我们根据已发表的信息绘制了纬度10°带内物种出现情况的经验分布，然后使用Chao2统计量推断该清单的完整性。我们发现海葵物种丰富度在北纬30 - 40°和南纬30 - 40°最高，热带地区数量较少，极地地区物种最少。Chao2统计量使我们能够推断，我们发现的丰富度模式并非由于对热带海葵了解特别匮乏。没有一个10°纬度带已知物种数量少于理论物种数量的60%，但只有大约一半的纬度带我们可以拒绝信息完整的零假设（P = 0.05）；海葵多样性在高纬度地区记录得最好。我们推断，目前已知的1089个有效物种约占海葵目约1500个理论物种总数的70%。海葵物种的分布模式与浮游有孔虫和底栖海藻的分布模式相似，尽管浮游细菌、海洋双壳类以及浅海和深海石珊瑚显示出赤道丰富度随纬度递减的陆地模式。在许多尺度上，海葵物种丰富度与石珊瑚的物种丰富度互补；我们的研究结果在全球尺度上证实了这一点。
