Predation changes the shape of thermal performance curves for population growth rate
Predation changes the shape of thermal performance curves for population growth rate
复制标题
捕食改变了种群增长率的热性能曲线的形状
作者：
T. M. Luhring;J. Delong
摘要体温通常表现为表现为温度的非线性变化(例如，运动速度、个体增长、种群增长)，其特征是热性能曲线(TPC)。捕食风险会引起表型和行为的改变，同样会影响绩效指标。我们测试了暴露于被捕食的小绿草履虫是否会影响原生动物澳大利亚草履虫的最大种群增长率(RMAX)TPC。我们将捕食者和非捕食者暴露在捕食者和非捕食者下的青草履虫种群增长率与先前显示的描述草履虫种群增长率TPC(LACTIN-2)的函数进行了拟合，并比较了曲线之间随后的参数估计。对于暴露于捕食风险的草履虫，与初始温度相比，最大种群增长随着温度的升高而增加得更快，随着温度的下降而下降得更快。每条TPC曲线下的面积保持大致相同，这与不同温度下性能权衡的想法一致。我们的结果表明，由于食物网络环境的变化，TPC是灵活的，营养相互作用可能在塑造TPC中发挥重要作用。此外，这项研究和其他研究表明，需要一种TPC的机械模型，其参数与生物学上有意义的特性有关。
Abstract Ectotherms generally demonstrate nonlinear changes in performance (e.g., movement speed, individual growth, population growth) as a function of temperature that are characterized by thermal performance curves (TPC). Predation risk elicits phenotypic and behavioral changes that likewise impact performance measures. We tested whether exposure to predation Orthocyclops modestus impacts the maximum population growth rate (rmax) TPC of the protist Paramecium aurelia. We fit predator and non-predator exposed P. aurelia population growth rates to a function previously shown to best describe Paramecium population growth rate TPC’s (Lactin-2) and compared subsequent parameter estimates between curves. For Paramecium exposed to predation risk, maximum population growth increased more rapidly as temperatures rose and decreased more rapidly as temperatures fell compared to the initial temperature. The area under each TPC curve remained approximately the same, consistent with the idea of a trade-off in performance across temperatures. Our results indicate TPCs are flexible given variation in food web context and that trophic interactions may play an important role in shaping TPCs. Furthermore, this and other studies illustrate the need for a mechanistic model of TPCs with parameters tied to biologically meaningful properties.