Data from: Comparative tests of the species-genetic diversity correlation at neutral and non-neutral loci in four species of stream insect

A fundamental question linking population genetics and community ecology is how adaptive processes (e.g., natural selection) and neutral processes (e.g., drift-migration equilibrium) underpin the species-genetic diversity correlation (SGDC). Here we combine genome scans and outlier loci detection with community analysis to separately test for neutral and non-neutral SGDCs in four species of stream insect. We sampled 60 localities in Japan and examined the relationships among population AFLP band richness (<i>Br</i>), taxon richness of the total community (<i>S</i>) and of the trophic guild (<i>S</i>_tr) richness, and 15 habitat parameters that could potentially drive adaptation and influence richness. Neutral <i>Br</i> was positively correlated with <i>S</i> only in the dominant species of these communities, suggesting <i>Br</i> may be constrained when intra-specific competition is pronounced. Non-neutral <i>Br</i> was correlated with <i>S</i>_tr in a species restricted to high elevations where habitat heterogeneity was highest. Community distance and genetic distance (β-SGDC) was correlated in two of the four species at both neutral and non-neutral loci. Distance-based redundancy analysis found geographic isolation and elevation to drive divergence of both communities and populations. This suggests that both neutral and adaptive divergence occurred through the shared influences of geographic isolation and local adaptation at the two levels of diversity.

联结种群遗传学与群落生态学的核心科学问题之一，是适应性过程（如自然选择）与中性过程（如漂变-迁移平衡）如何支撑物种-遗传多样性相关性（species-genetic diversity correlation, SGDC）。本研究将基因组扫描、异常位点检测与群落分析相结合，分别对4种溪流昆虫的中性与非中性SGDC进行检验。我们在日本境内共布设60个采样位点，检测了种群的AFLP条带丰富度（Br）、总群落类群丰富度（S）与营养功能群类群丰富度（S_tr）之间的关联，并分析了15项可能驱动适应性进程并影响丰富度的生境参数。仅在本研究群落的优势物种中，中性Br与S呈显著正相关，提示当种内竞争加剧时，Br可能受到约束。非中性Br仅在生境异质性最高的高海拔特有物种中，与S_tr呈相关关系。在4个物种中的2个物种内，群落距离与遗传距离（β-物种-遗传多样性相关性，β-species-genetic diversity correlation, β-SGDC）在中性及非中性位点均呈相关关系。基于距离的冗余分析（distance-based redundancy analysis）显示，地理隔离与海拔驱动了群落与种群的分化。这表明，中性与适应性分化均通过地理隔离与局部适应的共同作用，在两个多样性层面得以实现。