Adaptation and acclimation of traits associated with swimming capacity in Lake Whitefish (coregonus clupeaformis) ecotypes

BMC Evolutionary Biology

Research Article

Louis Bernatchez¹  Anne C. Dalziel²  Martin Laporte³  Nicolas Martin³ 

[1] Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Canada;Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Canada;Department of Biology, Saint Mary’s University, Halifax, NS, Canada;Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Canada;Department of Biology, Saint Mary’s University, Halifax, NS, Canada;School of Medicine, University of Wollongong, Northfields Avenue, 2522, Wollongong, NSW, Australia;

关键词: Phenotypic plasticity;    Local adaptation;    Ecophysiology;    Geometric morphometrics;    Speciation;    Parallel evolution;    Swimming cost;    Salmonidae;   

DOI  :  10.1186/s12862-016-0732-y

 received in 2016-03-09, accepted in 2016-08-01,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundImproved performance in a given ecological niche can occur through local adaptation, phenotypic plasticity, or a combination of these mechanisms. Evaluating the relative importance of these two mechanisms is needed to better understand the cause of intra specific polymorphism. In this study, we reared populations of Lake Whitefish (Coregonus clupeaformis) representing the’normal’ (benthic form) and the ‘dwarf’ (derived limnetic form) ecotypes in two different conditions (control and swim-training) to test the relative importance of adaptation and acclimation in the differentiation of traits related to swimming capacity. The dwarf whitefish is a more active swimmer than the normal ecotype, and also has a higher capacity for aerobic energy production in the swimming musculature. We hypothesized that dwarf fish would show changes in morphological and physiological traits consistent with reductions in the energetic costs of swimming and maintenance metabolism.ResultsWe found differences in traits predicted to decrease the costs of prolonged swimming and standard metabolic rate and allow for a more active lifestyle in dwarf whitefish. Dwarf whitefish evolved a more streamlined body shape, predicted to lead to a decreased drag, and a smaller brain, which may decrease their standard metabolic rate. Contrary to predictions, we also found evidence of acclimation in liver size and metabolic enzyme activities.ConclusionResults support the view that local adaptation has contributed to the genetically-based divergence of traits associated with swimming activity. Presence of post-zygotic barriers limiting gene flow between these ecotype pairs may have favoured repeated local adaptation to the limnetic niches.

【 授权许可】

CC BY   
© The Author(s). 2016