Data from: Antagonistic coevolution between quantitative and Mendelian traits

Coevolution is relentlessly creating and maintaining biodiversity, and therefore has been a central topic in evolutionary biology. Previous theoretical studies have mostly considered coevolution between genetically symmetric traits (i.e., coevolution between two continuous quantitative traits or two discrete Mendelian traits). However, recent empirical evidence indicates that coevolution can occur between genetically asymmetric traits (e.g., between quantitative and Mendelian traits). We examine consequences of antagonistic coevolution mediated by a quantitative predator trait and a Mendelian prey trait, such that predation is more intense with decreased phenotypic distance between their traits (phenotype matching). This antagonistic coevolution produces a complex pattern of bifurcations with bistability (initial state dependence) in a two-dimensional model for trait coevolution. Further, with eco-evolutionary dynamics (so that the trait evolution affects predator-prey population dynamics), we find that coevolution can cause rich dynamics including anti-phase cycles, in-phase cycles, chaotic dynamics, and deterministic predator extinction. Predator extinction is more likely to occur when the prey trait exhibits complete dominance rather than semidominance and when the predator trait evolves very rapidly. Our study illustrates how recognizing the genetic architectures of interacting ecological traits can be essential for understanding the population and evolutionary dynamics of coevolving species.

协同演化（coevolution）持续塑造并维系着生物多样性，因此始终是演化生物学领域的核心研究议题之一。此前的理论研究大多聚焦于遗传对称性状间的协同演化，即两类连续数量性状之间，或是两类离散孟德尔（Mendelian）性状之间的协同演化。然而，新近的实证研究表明，遗传不对称性状间同样可能发生协同演化，例如数量性状与孟德尔性状之间的协同演化。本研究针对由一类捕食者数量性状与一类猎物孟德尔性状介导的拮抗协同演化展开分析，其作用逻辑为：二者性状间的表型间距越小，捕食作用越强，即表型匹配效应。该类拮抗协同演化在二维性状协同演化模型中，会产生兼具双稳态（初始状态依赖性）的复杂分岔模式。进一步地，当纳入生态-演化动态（即性状演化会影响捕食者-猎物种群动态）时，本研究发现协同演化可催生丰富的动态行为，包括反相同步循环、同相同步循环、混沌动态，以及确定性捕食者灭绝事件。当猎物性状表现为完全显性而非半显性，且捕食者性状演化速率极快时，捕食者灭绝的发生概率会显著提升。本研究阐明，明确相互作用生态性状的遗传架构，对于理解协同演化物种种群动态与演化动态具有至关重要的意义。