Species' attributes predict the relative magnitude of ecological and genetic recovery following mass mortality

Theoretically, species' characteristics should allow estimation of dispersal potential and, in turn, explain levels of population genetic differentiation. However, a mismatch between traits and genetic patterns is often reported in marine species, and interpreted as evidence that life-history traits do not influence dispersal. Here, we couple ecological and genomic methods to test the hypothesis that species with attributes favoring greater dispersal potential -- e.g. longer pelagic duration, higher fecundity, and larger population size -- have greater realized dispersal overall. We used a natural experiment created by a large-scale and multi-species mortality event which created a 'clean slate' on which to study recruitment dynamics, thus simplifying a usually complex problem. We surveyed four species of differing dispersal potential to quantify the abundance and distribution of recruits and to genetically assign these recruits to likely parental sources. Species with higher dispersal potential re-colonized a broader extent of the impacted range, did so more quickly, and recovered more genetic diversity than species with lower dispersal potential. Moreover, populations of taxa with higher dispersal potential exhibited more immigration (71-92% of recruits) than taxa with lower dispersal potential (17-44% of recruits). By linking ecological with genomic perspectives, we demonstrate that a suite of interacting life history and demographic attributes do influence species' realized dispersal and genetic neighborhoods. To better understand species' resilience and recovery in this time of global change, integrative eco-evolutionary approaches are needed to more rigorously evaluate the effect of dispersal-linked attributes on realized dispersal and population genetic differentiation.

理论上，物种的特征本应可用于估算其扩散潜力，并进而阐释种群遗传分化的水平。然而，海洋物种中频繁报道存在性状与遗传模式之间的错配现象，此类现象常被解读为生活史性状（life-history traits）并不影响物种扩散的佐证。本研究结合生态学与基因组学方法，检验如下假说：具备更利于提升扩散潜力的属性——例如更长的浮游期（pelagic duration）、更高的繁殖力（fecundity）以及更大的种群规模——的物种，其整体实际扩散（realized dispersal）能力更强。我们依托一场大规模多物种死亡事件构建的自然实验（natural experiment）开展研究：该事件创造了一块原生种群被清除后的空白生境，可供开展种群补充动态（recruitment dynamics）研究，由此简化了这一通常极具复杂度的研究课题。我们选取四种扩散潜力各异的物种开展调查，以量化补充个体的丰度与分布格局，并通过遗传分析将这些补充个体归属至其可能的亲本种群来源。相较于扩散潜力较低的物种，具备较高扩散潜力的类群能够在受影响海域的更广范围内完成种群重新定殖，且定殖速度更快，恢复的遗传多样性也更为丰富。此外，扩散潜力较高的类群其种群表现出更高的迁入率（补充个体中71%~92%均来自外源迁入），而低扩散潜力类群的该比例仅为17%~44%。通过将生态学视角与基因组学视角相结合，我们证实了一系列相互关联的生活史与种群统计属性确实会对物种的实际扩散能力及遗传邻域（genetic neighborhoods）产生影响。为在全球变化时代更好地理解物种的恢复力与种群恢复过程，亟需采用整合性的生态-进化研究方法，以更严谨地评估与扩散相关的属性对实际扩散及种群遗传分化的影响。