The evolution of adaptive genetic variation in relation to speciation divergence and introgression in conifers

北方针叶树是自然分布最广的生物之一。它们通常具有高度的遗传多样性和基因流动。我们已经表明，历史一直是形成这种多样性的一个重要因素，因为在种内水平上存在着不同的遗传谱系，这些谱系是冰河时期由于地理分隔而出现的。这种隔离也可能导致了不同的适应，因为不同的气候是冰川避难所的特征，除了在全新世期间，随着冰川的退缩和冰川化，最近的自然选择。我们还表明，这种冰后期殖民也导致了杂交物种之间和种内谱系之间存在接触区，分别称为杂交区或缝合区。因此，遗传多样性可以在这些区域中高度结构化，对于不同的基因组甚至在核基因组内的基因组区域中观察到不同的模式。

Boreal conifers are among the living organisms with largest natural distributions. They are usually characterized by high genetic diversity and gene flow. We have shown that history has been an important factor in shaping this diversity given the existence of distinct geneticlineages at the intraspecific level, that have emerged as a result of vicariance during ice ages. This isolation may also have resulted in differential adaptation given thedifferent climates characterizing glacial refugia, in addition to more recent natural selection during Holocene, following the retreat of glaciers andrecolonization. We have also shown that this post-glacial colonization has also resulted in the existence of contact zones between hybridizing species andbetween intraspecific lineages, respectively called hybrid or suture zones. Therefore, genetic diversity can be highly structured in these zones, with different patterns observed for different genomes and even among genomic regions within the nuclear genome.