Chemical communication is critical in establishing angiosperm–pollinator mutualisms. However, our understanding of how chemical communication shapes coevolution remains limited. Here, we integrated information theory to model three coevolutionary scenarios (I‒III), where the pollinator fitness is always optimized by the highest certainty of chemical information provided by plants, but plant fitness is determined by (I) the certainty of chemical information attracting pollinators, (II) the uncertainty of chemical information confusing antagonists, or (III) both aspects. We found that the statistical properties of empirical plant volatiles from 45 pairs of fig–pollinator mutualisms were best explained by the selection from both pollinators and antagonists (scenario III). Under this scenario, plant–pollinator mutualisms evolve to be specialized and as few as two volatile chemicals could supply sufficient information for pollinators’ host identification. Our study provides new insights into plant–pollinator coevolution and will facilitate further studies on the evolution and diversification in specialized plant–pollinator–herbivore systems.

中文翻译：

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吸引传粉者和迷惑拮抗剂的选择使无花果-传粉者的化学通讯专门化

化学通讯对于建立被子植物-传粉者共生关系至关重要。然而，我们对化学通讯如何影响共同进化的理解仍然有限。在这里，我们整合了信息论来模拟三个共同进化场景 (I-III)，其中传粉者适应性总是由植物提供的化学信息的最高确定性来优化，但植物适应性由 (I) 化学信息吸引的确定性决定传粉者，（II）化学信息混淆拮抗剂的不确定性，或（III）两个方面。我们发现，来自 45 对无花果-传粉者共生体的经验植物挥发物的统计特性最好通过从传粉者和拮抗剂中进行选择来解释（情景 III）。在这种情况下，植物-传粉者互利共生进化为专门化，只要两种挥发性化学物质就可以为传粉者的宿主识别提供足够的信息。我们的研究为植物-传粉媒介协同进化提供了新的见解，并将促进对专门植物-传粉媒介-食草动物系统的进化和多样化的进一步研究。