Data from: Inconsistent reproductive isolation revealed by interactions between Catostomus fish species

Interactions between species are central to evolution and ecology, but we do not know enough about how outcomes of interactions between species vary across geographic locations, in heterogeneous environments, or over time. Ecological interactions between species are known to vary, but evolutionary interactions such as reproductive isolation are often assumed to be consistent. Hybridization among Catostomus fish species occurs over a large and heterogeneous geographic area and across taxa with distinct evolutionary histories, and allows us to assess consistency in species interactions. We analyzed hybridization among six Catostomus species and found extreme variation in hybridization across locations. Variation in hybridization outcomes might result from uneven fitness of hybrids across locations, polymorphism in genetic incompatibilities, chance, unidentified historical contingencies, or some combination thereof. Our results suggest caution in assuming that one or a few instances of hybridization represent all interactions between the focal species, as species interactions vary substantially across locations.物种间的相互作用是演化与生态学研究的核心议题，但目前我们对物种间相互作用的结果如何随地理区位、异质环境或时间推移发生变化仍所知有限。已知物种间的生态相互作用存在变异，但诸如生殖隔离这类演化相互作用通常被认为是恒定不变的。吸口鱼属（Catostomus）鱼类物种间的杂交发生于广阔且异质的地理区域内，且涉及具有不同演化历史的类群，这为我们评估物种相互作用的一致性提供了研究契机。我们对6种吸口鱼属鱼类的杂交情况展开分析，结果发现不同区位的杂交程度存在显著差异。杂交结果的变异可能源于不同区位中杂交后代适合度的不均一性、遗传不相容性的多态性、随机且未被探明的历史偶然性，或是上述因素的共同作用。我们的研究结果提示，倘若仅凭单个或少量杂交案例就推定其代表目标物种间的所有相互作用，需格外谨慎——因为物种相互作用在不同区位间存在显著差异。