Expanding the silverside system to quantify how climate gradients determine co- and countergradient adaptation strength in the ocean

许多物种已经进化出对纬度气候梯度的适应，研究这些变化有助于揭示物种将如何进化以应对全球气候变化。为了研究智利银鱼的适应性，来自智利海岸四个地点的野生鱼的后代在四种常见温度下饲养。来自不同纬度的种群之间的生长率、脊椎数和汞摄取量的差异表明，由于当地适应的原因，遗传差异。研究小组正在将智利的这些银边数据与北半球银边物种的先前数据进行整合，以更好地了解气候梯度强度和适应强度之间的关系。该项目通过美国-智利研究生跨文化交流为两名研究生提供培训。这项研究正在被整合到智利教授的研究生和本科课程中，研究小组正在通过一个网站和杂志文章与公众分享研究结果。该项目促进了对两种形式的局部适应的理解，即共梯度变化(CoGV)和逆梯度变化(CnGV)，它们是适应大规模纬向气候梯度的基础。通过一个普通的园艺实验，研究小组正在研究温度和智利银鱼遗传变异之间的关系。从智利沿海四个地点的野生创业者那里获得的新受精后代正在四个普通温度下饲养，达到普通的幼体大小。不同种群在性状测量(生长能力、脊椎数和总汞浓度)方面的差异，以检验以下假设：1)生长能力随温度和纬度(CnGV)增加，2)脊椎数随纬度(CoGV)增加。这些数据正在与北半球银边物种的现有证据相结合，以确定CnGV/CoGV强度和纬度梯度强度之间是否存在关系。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Many species have evolved adaptations to latitudinal climate gradients and studying these sheds light on how species will evolve in response to global climate change. To investigate adaptation in Chilean silversides, offspring of wild fish from four locations along the Chilean coast are being reared at four common temperatures. Differences in growth rates, vertebral number, and mercury uptake among populations from different latitudes indicate genetic differences due to local adaptation. The research team is integrating these Chilean silverside data with prior data from northern hemisphere silverside species to better understand the relationship between climate gradient strength and adaptation strength. This project provides training for two graduate students through a US-Chile graduate cross-cultural exchange. The research is being integrated into graduate and undergraduate courses taught in Chile and the research team is sharing the results with the public through a website and magazine articles. This project advances understanding of two forms of local adaptation, co-gradient variation (CoGV) and counter-gradient variation (CnGV), which underlie adaptation to large-scale, latitudinal climate gradients. Using a common garden experiment, the team is examining the relationship between temperature and genetic variation in Chilean silversides. Newly-fertilized offspring obtained from wild founders at four locations along the Chilean coast are being reared at four common temperatures to a common juvenile size. Differences among populations in trait measurements (growth capacity, vertebral number, and total mercury concentration) to test the hypotheses that 1) growth capacity increases with temperature and latitude (CnGV) and 2) vertebral number increases with latitude (CoGV). These data are being integrated with existing evidence from northern hemisphere silverside species to determine if there is a relationship between CnGV/CoGV strength and latitudinal gradient strength.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.