Behavioral constraints on local adaptation and counter-gradient variation: implications for climate change

Resource allocation to growth, reproduction, and body maintenance varies within species along latitudinal gradients. Two hypotheses explaining this variation are local adaptation and counter-gradient variation. The local adaptation hypothesis proposes that populations are adapted to local environmental conditions and are therefore less adapted to environmental conditions at other locations. The counter-gradient variation hypothesis proposes that one population out performs others across an environmental gradient because its source location has greater selective pressure than other locations. Our study had two goals. First, we tested the local adaptation and counter-gradient variation hypotheses by measuring effects of environmental temperature on phenotypic expression of reproductive traits in the burying beetle, Nicrophorus orbicollis Say, from three populations along a latitudinal gradient in a common garden experimental design. Second, we compared patterns of variation to evaluate wh...

物种内用于生长、繁殖与机体维持的资源分配，会随纬度梯度发生变化。解释这一差异的两种假说分别为本地适应（local adaptation）与反梯度变异（counter-gradient variation）。本地适应假说提出，种群仅适应其原生地的环境条件，因此对其他区域的环境适应性较弱。反梯度变异假说则认为，在环境梯度上某一种群的表现优于其他种群，原因是其起源地的选择压力高于其他区域。本研究包含两个目标：其一，我们采用同质园实验设计，对沿纬度梯度分布的3个埋葬甲（Nicrophorus orbicollis Say）种群的繁殖性状表型表达受环境温度的影响进行测定，以此验证本地适应与反梯度变异假说；其二，我们通过对比变异模式以评估……