Data from: How mechanisms of habitat preference evolve and promote divergence with gene flow

Habitat preference may promote adaptive divergence and speciation, yet the conditions under which this is likely are insufficiently explored. We use individual-based simulations to study the evolution and consequence of habitat preference during divergence with gene flow, considering four different underlying genetically-based behavioral mechanisms: natal habitat imprinting, phenotype-dependent, competition-dependent, and direct genetic habitat preference. We find that the evolution of habitat preference generally requires initially high dispersal, is facilitated by asymmetry in population sizes between habitats, and is hindered by an increasing number of underlying genetic loci. Moreover, the probability of habitat preference to emerge and promote divergence differs greatly among the underlying mechanisms. Natal habitat imprinting evolves most easily and can allow full divergence in parameter ranges where no divergence is possible in the absence of habitat preference. The reason is that imprinting represents a one-allele mechanism of assortative mating linking dispersal behavior very effectively to local selection. At the other extreme, direct genetic habitat preference, a two-allele mechanism, evolves under restricted conditions only, and even then facilitates divergence weakly. Overall, our results indicate that habitat preference can be a strong reproductive barrier promoting divergence with gene flow, but that this is highly contingent on the underlying preference mechanism.生境偏好可促进适应性分化与物种形成，但目前学界对其得以实现的具体条件仍缺乏充分探索。本研究采用基于个体的模拟实验，探究存在基因流的分化过程中生境偏好的演化及其效应，共考量四种不同的基于遗传的行为调控机制：出生生境印记（natal habitat imprinting）、表型依赖型、竞争依赖型以及直接遗传型生境偏好（direct genetic habitat preference）。研究结果显示，生境偏好的演化通常需要初始阶段具备较高的扩散水平，生境间种群规模的不对称性可推动该演化过程，而调控其的遗传位点数量增多则会阻碍其演化。此外，不同调控机制下，生境偏好演化并促进分化的概率存在显著差异。其中出生生境印记最易发生演化，且在无生境偏好时无法产生分化的参数区间内，仍可促成完全的适应性分化。究其原因，印记机制属于单等位基因选型交配机制，可将扩散行为与局域选择高效关联起来。与之截然相反的直接遗传型生境偏好属于双等位基因机制，仅能在有限条件下发生演化，且即便成功演化，其促进分化的效果也较为微弱。综合来看，本研究结果表明，生境偏好可作为一道强大的生殖屏障，在存在基因流的情况下推动种群分化，但这一效应高度依赖于其所依托的偏好调控机制。