PDF(Pubmed)
Abstract：
Understanding the dispersal potential of different species is essential for predicting recovery trajectories following local disturbances and the potential for adaptive loci to spread to populations facing extreme environmental changes. However, dispersal distances have been notoriously difficult to estimate for scleractinian corals, where sexually (as gametes or larvae) or asexually (as fragments or larvae) derived propagules disperse through vast oceans. Here, we demonstrate that generational dispersal distances for sexually produced propagules can be indirectly inferred for corals using individual-based isolation-by-distance (IbD) analyses by combining reduced-representation genomic sequencing with photogrammetric spatial mapping. Colonies from the genus Agaricia were densely sampled across plots at four locations and three depths in Curaçao. Seven cryptic taxa were found among the three nominal species (Agaricia agaricites, Agaricia humilis and Agaricia lamarcki), with four taxa showing generational dispersal distances within metres (two taxa within A. agaricites and two within A. humilis). However, no signals of IbD were found in A. lamarcki taxa and thus these taxa probably disperse relatively longer distances. The short distances estimated here imply that A. agaricites and A. humilis populations are reliant on highly localized replenishment and demonstrate the need to estimate dispersal distances quantitatively for more coral species.
摘要：
了解不同物种的扩散潜力对于预测局部干扰后的恢复轨迹以及适应性基因座扩散到面临极端环境变化的种群的可能性至关重要。然而,众所周知，对于巩膜珊瑚来说，扩散距离很难估计，有性（作为配子或幼虫）或无性（作为碎片或幼虫）衍生的繁殖体散布在广阔的海洋中。这里,我们证明，通过将简化表示的基因组测序与摄影测量空间作图相结合，使用基于个体的距离隔离（IbD）分析，可以间接推断珊瑚有性繁殖繁殖体的世代扩散距离。在库拉索岛的四个位置和三个深度的地块上，对Agaricia属的菌落进行了密集采样。在三个名义物种（AgariciaAgaricites，Agariciahumilis和Agaricialamarcki)，四个分类单元显示出数米之内的世代扩散距离（两个分类单元在A.Agaricites中，两个分类单元在A.humilis中）。然而,在A.lamarcki分类单元中未发现IbD信号，因此这些分类单元可能分散相对较长的距离。此处估计的短距离意味着A.Agaricites和A.humilis种群依赖于高度局部的补给，并表明需要定量估计更多珊瑚物种的扩散距离。
