Olsen Esben Moland, Knutsen Halvor, Gjøsæter Jakob, Jorde Per Erik, Knutsen Jan Atle, Stenseth Nils Chr
Institute of Marine Research Flødevigen, His, Norway.
Institute of Marine Research Flødevigen, His, Norway ; Centre for Ecological and Evolutionary Synthesis (CEES), Department of Biology, University of Oslo Blindern, Oslo, Norway.
Evol Appl. 2008 Aug;1(3):524-33. doi: 10.1111/j.1752-4571.2008.00024.x.
Harvesting of marine resources raises concerns about how to identify and preserve biocomplexity, including the diversity of life histories found within and among wild populations of a species. In order to fully accomplish this, there is a need to elucidate the underlying causes of phenotypic variation, and how this variation responds to environmental changes. In general, both evolutionary (genetic) and nonevolutionary (plastic) responses may occur. Plastic responses to environmental change are expected to shift the phenotype along a reaction norm, while an evolutionary response is expected to shift the reaction norm itself. Here, we assess the maturation patterns of coastal Atlantic cod (Gadus morhua) in Skagerrak, where studies using neutral markers have revealed genetically differentiated populations of this harvested fish within tens of kilometres of coastline. Our results suggest that physiological state prior to the spawning season, as well as juvenile growth, both influence the probability of completing sexual maturation at a given age. Furthermore, our results point towards a spatial structuring of this plasticity (i.e. the maturation reaction norms) comparable with population connectivity inferred from neutral markers. We argue that such fine-scale biocomplexity calls for a Darwinian approach to fisheries management.
海洋资源的捕捞引发了人们对如何识别和保护生物复杂性的担忧，这其中包括一个物种野生种群内部和之间存在的生活史多样性。为了全面实现这一点，有必要阐明表型变异的根本原因，以及这种变异如何应对环境变化。一般来说，可能会出现进化（遗传）和非进化（可塑性）两种反应。对环境变化的可塑性反应预计会使表型沿着反应规范发生变化，而进化反应预计会使反应规范本身发生变化。在此，我们评估了斯卡格拉克海峡沿海大西洋鳕鱼（Gadus morhua）的成熟模式，在那里，使用中性标记的研究表明，在海岸线几十公里范围内，这种被捕捞鱼类存在遗传分化的种群。我们的结果表明，产卵季节前的生理状态以及幼鱼生长，都会影响在特定年龄完成性成熟的概率。此外，我们的结果表明这种可塑性（即成熟反应规范）存在空间结构，这与从中性标记推断出的种群连通性相当。我们认为，这种精细尺度的生物复杂性需要一种达尔文式的渔业管理方法。
