Manenti Tommaso, Sørensen Jesper G, Loeschcke Volker
Section for Genetics, Ecology and Evolution Department of Bioscience Aarhus University Aarhus C Denmark.
Ecol Evol. 2017 Mar 19;7(8):2716-2724. doi: 10.1002/ece3.2904. eCollection 2017 Apr.
Adaptation of natural populations to variable environmental conditions may occur by changes in trait means and/or in the levels of plasticity. Theory predicts that environmental heterogeneity favors plasticity of adaptive traits. Here we investigated the performance in several traits of three sympatric species freshly collected in two environments that differ in the heterogeneity of environmental conditions. Differences in trait means within species were found in several traits, indicating that populations differed in their evolutionary response to the environmental conditions of their origin. Different species showed distinct adaptation with a very different role of plasticity across species for coping with environmental changes. However, geographically distinct populations of the same species generally displayed the same levels of plasticity as induced by fluctuating thermal regimes. This indicates a weak and trait-specific effect of environmental heterogeneity on plasticity. Furthermore, similar levels of plasticity were found in a laboratory-adapted population of with a common geographic origin but adapted to the laboratory conditions for more than 100 generations. Thus, this study does not confirm theoretical predictions on the degree of adaptive plasticity among populations in relation to environmental heterogeneity but shows a very distinct role of species-specific plasticity.
自然种群对多变环境条件的适应可能通过性状均值的变化和/或可塑性水平的变化来实现。理论预测，环境异质性有利于适应性性状的可塑性。在此，我们研究了在环境条件异质性不同的两种环境中新鲜采集的三个同域物种在几个性状上的表现。在几个性状中发现了物种内性状均值的差异，这表明种群对其原生环境条件的进化反应有所不同。不同物种表现出不同的适应性，在应对环境变化时，可塑性在不同物种中发挥着截然不同的作用。然而，同一物种在地理上不同的种群通常表现出与波动热环境诱导的相同水平的可塑性。这表明环境异质性对可塑性的影响微弱且具有性状特异性。此外，在一个来自共同地理起源但已适应实验室条件100多代的实验室适应种群中，发现了相似水平的可塑性。因此，本研究并未证实关于种群间适应性可塑性程度与环境异质性关系的理论预测，而是显示了物种特异性可塑性的非常独特的作用。
