Data from: The sex chromosome system can influence the evolution of sex-biased dispersal

Sex-biased dispersal is a much-discussed feature in literature on dispersal. Diverse hypotheses have been proposed to explain the evolution of sex-biased dispersal, a difference in dispersal rate or dispersal distance between males and females. An early hypothesis has indicated that it may rely on the difference in sex chromosomes between males and females. However, this proposal was quickly rejected without a real assessment. We propose a new perspective on this hypothesis by investigating the evolution of sex-biased dispersal when dispersal genes are sex-linked, i.e. when they are located on the sex chromosomes. We show that individuals of the heterogametic sex disperse relatively more than do individuals of the homogametic sex when dispersal genes are sex-linked rather than autosomal. Although such a sex-biased dispersal towards the heterogametic sex is always observed in monogamous species, the mating system and the location of dispersal genes interact to modulate sex-biased dispersal in monandry and polyandry. In the context of the multicausality of dispersal, we suggest that sex-linked dispersal genes can influence the evolution of sex-biased dispersal.

性偏扩散（Sex-biased dispersal）是扩散研究领域文献中广受讨论的核心议题。学界已提出多种假说，用以阐释性偏扩散的演化机制——即雄性与雌性在扩散速率或扩散距离上存在的系统性差异。早期有假说提出，性偏扩散可能源于雌雄个体间的性染色体差异，然而该假说尚未经过严谨的实证评估便被迅速否定。本研究针对该假说提出全新视角，聚焦于扩散基因为性连锁（sex-linked，即位于性染色体上）时的性偏扩散演化过程。研究结果表明：当扩散基因为性连锁而非常染色体连锁时，异配性别（heterogametic sex）个体的扩散比例相对高于同配性别（homogametic sex）个体。尽管在单配制物种中始终能观察到偏向异配性别的性偏扩散现象，但交配系统与扩散基因位置的交互作用，会在单雄交配与多雄交配体系中调控性偏扩散的模式。鉴于扩散演化具有多因性的特征，本研究认为性连锁扩散基因可对性偏扩散的演化产生影响。