Thompson John N, Schwind Christopher, Friberg Magne
Am Nat. 2017 Aug;190(2):171-184. doi: 10.1086/692164. Epub 2017 May 8.
Closely related species often have similar traits and sometimes interact with the same species. A crucial problem in evolutionary ecology is therefore to understand how coevolving species diverge when they interact with a set of closely related species from another lineage rather than with a single species. We evaluated geographic differences in the floral morphology of all woodland star plant species (Lithophragma, Saxifragaceae) that are pollinated by Greya (Prodoxidae) moths. Flowers of each woodland star species differed depending on whether plants interact locally with one, two, or no pollinating moth species. Plants of one species grown in six different environments showed few differences in floral traits, suggesting that the geographic differences are not due significantly to trait plasticity. Greya moth populations also showed significant geographic divergence in morphology, depending on the local host and on whether the moth species co-occurred locally. Divergence in the plants and the moths involved shifts in combinations of partially correlated traits, rather than any one trait. The results indicate that the geographic mosaic of coevolution can be amplified as coevolving lineages diversify into separate species and come together in different combinations in different ecosystems.
亲缘关系相近的物种通常具有相似的特征，有时还会与同一物种相互作用。因此，进化生态学中的一个关键问题是要理解，当共同进化的物种与来自另一个谱系的一组亲缘关系相近的物种而非单个物种相互作用时，它们是如何分化的。我们评估了所有由灰蝶（Prodoxidae）授粉的林地星属植物（Lithophragma，虎耳草科）花部形态的地理差异。每个林地星属物种的花因植物在当地与一种、两种或不与任何授粉蛾类物种相互作用而有所不同。在六种不同环境中生长的一个物种的植物在花部特征上几乎没有差异，这表明地理差异并非主要归因于性状可塑性。灰蝶种群在形态上也表现出显著的地理分化，这取决于当地的寄主以及该蛾类物种是否在当地同时出现。植物和蛾类的分化涉及部分相关性状组合的变化，而非任何单一性状。结果表明，随着共同进化的谱系分化为不同物种并在不同生态系统中以不同组合聚集在一起，共同进化的地理镶嵌模式可能会被放大。
