The Geographic Scale of Larval Dispersal

预计幼虫的运动模式和扩散的空间规模将是调节海洋系统中种群和群落动态的主要力量。大多数海洋物种的生活史都包括一个能够在广阔地理区域内扩散的幼虫阶段，了解这些物种种群动态的努力受到浮游营养化发展中固有的幼虫扩散幅度的阻碍。幼虫扩散规模是了解海洋物种补充动态的关键参数。我们将利用在两种贻贝杂交区形成的遗传镶嵌来评估幼虫扩散的地理规模。在这个系统中，大量的幼虫在特定的位置产生，具有不同的遗传特征，并释放到浮游生物中。通过监测这些“标记”幼虫的沉降，我们将评估幼虫扩散的地理规模和动态。在这项研究中，我们将利用分子遗传标记，这是我们在生物海洋学之前的支持下开发的，它允许确定贻贝幼虫或贝的种群遗传学。通过利用我们已经开发的分子遗传标记，以及由贻贝物种之间杂交形成的遗传马赛克的存在，将有可能监测幼虫在地理区域之间的运动。利用该系统，我们将确定幼虫扩散的地理尺度、扩散能力的时空变化，并验证幼虫运动模式主要受局部循环动力学控制的假设。

Patterns of larval movement and the spatial scale of dispersal are expected to be major forces in regulating the dynamics of populations and communities in marine systems. The life history of most marine species includes a larval stage that is capable of dispersal over broad geographic areas and efforts to understand the population dynamics of these species have been stymied by the magnitude of larval dispersal inherent in planktotrophic development. The scale of larval dispersal is a key parameter in understanding the recruitment dynamics of marine species. We will exploit the genetic mosaics formed in a hybrid zone between two species of mussels to assess the geographic scale of larval dispersal. In this system, large numbers of larvae are produced at specific locations with distinct genetic signatures and released into the plankton. By monitoring the settlement of these `marked` larvae we will assess the geographic scale and dynamics of larval dispersal. In this study we will capitalize on molecular genetic markers, that we have developed with previous support from Biological Oceanography, that allow the population genetics of mussel larvae or spat to be determined. By exploiting both the molecular genetic markers we have developed, and the presence of genetic mosaics formed by hybridization between mussel species it will be possible to monitor the movement of larvae between geographic areas. Using this system we will determine the geographic scale of larval dispersal, spatial and temporal variation in dispersal capacity and test the hypothesis that patterns of larval movement are predominantly controlled by local circulation dynamics.