Chemical communication, sexual selection, and introgression in wall lizards

Divergence in communication systems should influence the likelihood that individuals from different lineages interbreed, and consequently shape the direction and rate of hybridization. Here, we studied the role of chemical communication in hybridization, and its contribution to asymmetric and sexually selected introgression, between two lineages of the common wall lizard (Podarcis muralis). Males of the two lineages differed in the chemical composition of their femoral secretions. Chemical profiles provided information regarding male secondary sexual characters, but the associations were variable and inconsistent between lineages. In experimental contact zones, chemical composition was weakly associated with male reproductive success, and did not predict the likelihood of hybridization. Consistent with these results, introgression of chemical profiles in a natural hybrid zone resembled that of neutral nuclear genetic markers overall, but one compound in particular (tocopherol methyl eth...通讯系统的分化会影响不同演化支个体间的杂交繁殖概率，并进而塑造杂交的方向与速率。本研究以普通壁蜥（Podarcis muralis）的两个演化支为对象，探究了化学通讯在杂交过程中的作用，及其对不对称渐渗与性选择渐渗的贡献。两个演化支的雄性个体其股腺分泌物的化学成分存在显著差异。化学成分谱能够反映雄性第二性征的相关信息，但不同演化支间的关联模式存在变异且并不一致。在实验接触带中，化学成分仅与雄性繁殖成功率存在微弱关联，且无法预测杂交发生的概率。与上述结果一致，自然杂交带中化学成分谱的渐渗总体上与中性核遗传标记的渐渗模式相似，但其中某一类化合物（生育酚甲基醚……）