Balázs Gergely, Biró Anna, Fišer Žiga, Fišer Cene, Herczeg Gábor
Behavioural Ecology Group Department of Systematic Zoology and Ecology ELTE Eötvös Loránd University Budapest Hungary.
Department of Biology Biotechnical Faculty University of Ljubljana Ljubljana Slovenia.
Ecol Evol. 2021 Oct 20;11(21):15389-15403. doi: 10.1002/ece3.8233. eCollection 2021 Nov.
Studying parallel evolution (repeated, independent evolution of similar phenotypes in similar environments) is a powerful tool to understand environment-dependent selective forces. Surface-dwelling species that repeatedly and independently colonized caves provide unique models for such studies. The primarily surface-dwelling species complex is a good candidate to carry out such research, because it colonized several caves in Europe. By comparing 17 functional morphological traits between six cave and nine surface populations of the species complex, we investigated population divergence in morphology and sexual dimorphism. We found habitat-dependent population divergence in 10 out of 17 traits, likely reflecting habitat-driven changes in selection acting on sensory systems, feeding, grooming, and antipredator mechanisms. Sexual dimorphism was present in 15 traits, explained by sexual selection acting on male traits important in male-male agonistic behavior or mate guarding and fecundity selection acting on female traits affecting offspring number and nursing. In eight traits, the degree of sexual dimorphism was habitat dependent. We conclude that cave-related morphological changes are highly trait- and function-specific and that the strength of sexual/fecundity selection strongly differs between cave and surface habitats. The considerable population variation within habitat type warrants further studies to reveal cave-specific adaptations besides the parallel patterns.
研究平行进化（在相似环境中相似表型的重复、独立进化）是理解环境依赖性选择力的有力工具。反复且独立地定殖于洞穴的地表栖息物种为此类研究提供了独特的模型。主要栖息于地表的物种复合体是开展此类研究的理想候选对象，因为它在欧洲的多个洞穴中定殖。通过比较该物种复合体的六个洞穴种群和九个地表种群之间的17个功能形态特征，我们研究了形态学上的种群分化和两性异形。我们发现，在17个特征中有10个存在依赖于栖息地的种群分化，这可能反映了作用于感觉系统、摄食、梳理毛发和反捕食机制的选择中由栖息地驱动的变化。15个特征中存在两性异形，这可以由作用于在雄性间争斗行为或配偶保卫中重要的雄性特征的性选择以及作用于影响后代数量和哺育的雌性特征的繁殖力选择来解释。在八个特征中，两性异形的程度依赖于栖息地。我们得出结论，与洞穴相关的形态变化具有高度的特征和功能特异性，并且性/繁殖力选择的强度在洞穴和地表栖息地之间存在很大差异。栖息地类型内相当大的种群变异值得进一步研究，以揭示除了平行模式之外的洞穴特异性适应。
