Arctic and sub-Arctic ecosystems are rapidly changing, but morphological diversity can increase a species’ resilience to these environmental fluctuations. Capelin Mallotus villosus is a cold-water forage fish distributed throughout the northern hemisphere, but is not thoroughly studied outside the Atlantic Ocean, which impedes our ability to infer the functional significance of morphometric variation among populations. The objective of this study was to use relative warps, a comprehensive geometric morphometric method, to determine if capelin populations could be distinguished by beach spawning location in the western Canadian Arctic (one location), Newfoundland, Canada (three locations), and Alaska, USA (two locations). Morphometry was examined separately by sex and compared among and within geographic regions using relative warp analysis (RWA), Procrustes ANOVA, estimates of morphological disparity, and canonical variates analysis (CVA). For both sexes, capelin from the western Canadian Arctic were differentiated from other regions, primarily by pelvic fin location. Within Newfoundland, capelin from Witless Bay, Bellevue Beach (males only), and Middle Cove were only distinguishable from each other using CVA. Within Alaska, males from Norton Sound were distinct from Prince William Sound using RWA and CVA. When all subregions were examined together, evidence for population separation was weaker for both sexes than when regions or subregions were examined separately. These morphological variations imply diversity throughout this species’ geographic distribution. Biological attributes (e.g., total length, weight, fecundity), which are influenced by multiple environmental factors such as prey availability, also varied among and within regions and may explain some of the identified morphometric diversity.

中文翻译：

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使用相对经线的区域间和区域内的毛鳞鱼绒毛种群分化

北极和亚北极生态系统正在迅速变化，但形态多样性可以提高物种对这些环境波动的适应能力。Capelin Mallotus villosus 是一种分布在整个北半球的冷水饲料鱼，但没有在大西洋以外进行彻底的研究，这阻碍了我们推断种群间形态变异的功能意义的能力。本研究的目的是使用相对扭曲，一种综合几何形态测量方法，以确定是否可以通过加拿大西部北极（一个位置）、加拿大纽芬兰（三个位置）和阿拉斯加的海滩产卵位置区分毛鳞鱼种群，美国（两个地点）。形态测量按性别分别进行检查，并使用相对扭曲分析 (RWA) 在地理区域之间和地理区域内进行比较，Procrustes 方差分析、形态差异估计和规范变量分析 (CVA)。对于两性，来自加拿大西部北极地区的毛鳞鱼与其他地区的区别主要在于腹鳍位置。在纽芬兰，来自 Witless Bay、Bellevue Beach（仅限男性）和 Middle Cove 的毛鳞鱼只能使用 CVA 进行区分。在阿拉斯加，使用 RWA 和 CVA，诺顿湾的雄性与威廉王子湾的雄性截然不同。将所有次区域一起检查时，两性人口分离的证据比单独检查区域或次区域时要弱。这些形态变化意味着该物种地理分布的多样性。生物属性（例如，总长度、重量、繁殖力），