Initial genetic diversity enhances population establishment and alters genetic structuring of a newly established Daphnia metapopulation

When newly created habitats are initially colonized by genotypes with rapid population growth rates, later arriving colonists may be prevented from establishing. Although these priority effects have been documented in multiple systems, their duration may be influenced by the diversity of the founding population. We conducted a large-scale field manipulation to investigate how initial clonal diversity influences temporal and landscape patterns of genetic structure in a developing metapopulation. Six genotypes of obligately asexual Daphnia pulex were stocked alone (no clonal diversity) or in combination (‘high’ clonal diversity) into newly created experimental woodland ponds. We also measured the population growth rate of all clones in the laboratory when raised on higher-quality and lower-quality resources. Our predictions were that in the 3 years following stocking, clonally diverse populations would be more likely to persist than nonclonally diverse populations and exhibit evidence for...

当新创建的生境最初被种群增长速率较快的基因型定植后，后续抵达的定植者可能无法成功建立种群。尽管这类优先效应（priority effects）已在多种生态系统中被观测记录，但其持续时长可能受建群种群多样性的调控。本研究开展了大规模野外操控实验，以探究初始克隆多样性如何影响发育中集合种群（metapopulation）的遗传结构的时间格局与景观格局。我们将专性无性生殖的蚤状溞（Daphnia pulex）的6种基因型，以单一基因型（无克隆多样性）或多基因型组合（高克隆多样性）的方式，投放至新创建的实验林地池塘中。我们还在实验室中测定了所有克隆株系在优质与劣质饵料资源下的种群增长速率。我们提出的研究假设为：在投放后的3年内，具有克隆多样性的种群将比无克隆多样性的种群更易持续存活，并表现出相关的遗传证据（原文后半段未完整给出）