SGER: Dispersal of Planktonic Invertebrate Larvae and the Biogeography of the Antarctic Benthos

SGER：浮游无脊椎动物幼虫的传播和南极底栖生物地理学

• 批准号: 9910164
• 负责人: Rudolf Scheltema
• 金额: $ 5.64万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-10-01 至 2005-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9910164&HistoricalAwards=false
• 关键词: SGER; Dispersal; Planktonic; Invertebrate; Larvae

AbstractOPP99-10164P.I. Rudolf ScheltemaBecause of the extreme isolation of Antarctica since the early Oligocene one can expect to encounter a unique invertebrate fauna with a high degree of endemism. Yet, some benthic taxa include from 20 to 50 percent non-endemic species. To account for such species it has been proposed that an intermittent reciprocal exchange must occur between the antiboreal populations of South America and the Antarctic continent. One possible means by which the geographical distribution can be maintained and genetic exchange may be accomplished is by the passive dispersal of planktonic larvae. To show that such dispersal is actually accomplished it must be demonstrated that (1) larvae of sublittoral species actually are found within the Drake passage and that such larvae belong to species that occur both in the antiboreal South American and Antarctic faunas and (2) that a hydrographic mechanism exists that can explain how the passive transport of larvae may occur between the two continents. The proposed research will address these two requirements by making transects of plankton samples across the Drake passage and by examining the possibility of cross frontal exchange of larvae at the subantarctic and polar fronts of the Antarctic circumpolar current as well as the possible transport of larvae in mesoscale rings. The outcome may suggest species that in the future may profitably be examined using molecular techniques, comparing individuals from bottom populations of South America and Antarctica. The study necessarily must be of a very preliminary nature since the occurrence of planktonic larvae of sublittoral benthic species in the Drake Passage has never before been examined.

鲁道夫·谢尔特马由于南极洲自渐新世早期以来极度孤立，人们可能会遇到一种独特的、具有高度地方性的无脊椎动物。然而，一些底栖生物分类群包括20%到50%的非特有物种。为了解释这些物种，有人提出，南美洲和南极大陆的反生物种群之间必须进行断断续续的互换。维持地理分布和完成遗传交流的一种可能方法是通过浮游幼虫的被动扩散。为了证明这种扩散实际上是完成的，必须证明：(1)潮下物种的幼虫实际上是在德雷克海峡内发现的，而且这种幼虫属于同时出现在南美洲和南极反大陆动物群中的物种，以及(2)存在一种水文机制，可以解释两个大陆之间如何发生幼虫的被动运输。拟议的研究将通过制作横跨德雷克海峡的浮游生物样本和检查在南极绕极洋流的亚极锋和极锋的幼虫跨锋面交换的可能性以及幼虫在中尺度环中的可能运输来满足这两个要求。结果可能表明，未来可能会使用分子技术来研究那些有利可图的物种，比较南美洲和南极洲底层种群的个体。这项研究必须是非常初步的性质，因为以前从未研究过德雷克航道中出现过潮下底栖物种的浮游幼虫。