Raeymaekers Joost A M, Chaturvedi Anurag, Hablützel Pascal I, Verdonck Io, Hellemans Bart, Maes Gregory E, De Meester Luc, Volckaert Filip A M
Laboratory of Biodiversity and Evolutionary Genomics, KU Leuven, B-3000, Leuven, Belgium.
Centre for Biodiversity Dynamics, Department of Biology, Norwegian University of Science and Technology, N-7491, Trondheim, Norway.
Nat Commun. 2017 Aug 16;8(1):267. doi: 10.1038/s41467-017-00256-6.
Species in a common landscape often face similar selective environments. The capacity of organisms to adapt to these environments may be largely species specific. Quantifying shared and unique adaptive responses across species within landscapes may thus improve our understanding of landscape-moderated biodiversity patterns. Here we test to what extent populations of two coexisting and phylogenetically related fishes-three-spined and nine-spined stickleback-differ in the strength and nature of neutral and adaptive divergence along a salinity gradient. Phenotypic differentiation, neutral genetic differentiation and genomic signatures of adaptation are stronger in the three-spined stickleback. Yet, both species show substantial phenotypic parallelism. In contrast, genomic signatures of adaptation involve different genomic regions, and are thus non-parallel. The relative contribution of spatial and environmental drivers of population divergence in each species reflects different strategies for persistence in the same landscape. These results provide insight in the mechanisms underlying variation in evolutionary versatility and ecological success among species within landscapes.The three-spined stickleback is a model species for the study of adaptive divergence. Here, Raeymaekers et al. compare how the three-spined stickleback and its relative the nine-spined stickleback vary at the phenotypic and genomic levels in response to the same spatial and environmental drivers.
在同一景观中的物种通常面临相似的选择环境。生物体适应这些环境的能力可能在很大程度上具有物种特异性。因此，量化景观中不同物种间共享的和独特的适应性反应，可能会增进我们对景观调节的生物多样性模式的理解。在此，我们测试了两种共存且具有系统发育关系的鱼类——三刺鱼和九刺鱼——的种群，在沿着盐度梯度的中性和适应性分化的强度及性质方面有多大差异。三刺鱼的表型分化、中性遗传分化和适应性的基因组特征更强。然而，两个物种都表现出显著的表型平行性。相比之下，适应性的基因组特征涉及不同的基因组区域，因此是非平行的。每个物种中种群分化的空间和环境驱动因素的相对贡献，反映了在同一景观中持续存在的不同策略。这些结果为景观中物种间进化通用性和生态成功的变异背后的机制提供了见解。三刺鱼是研究适应性分化的模式物种。在此，雷马克斯等人比较了三刺鱼及其近亲九刺鱼在表型和基因组水平上如何响应相同的空间和环境驱动因素。
