Centre d'Ecologie Fonctionnelle et Evolutive, CNRS, Université de Montpellier, 1919 Route de Mende, 34293 Montpellier Cedex 5, France
Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary, and Life Sciences, University of Glasgow, Graham Kerr Building, Glasgow G12 8QQ, UK.
Proc Biol Sci. 2017 Nov 29;284(1867). doi: 10.1098/rspb.2017.1411.
Most population dynamics studies assume that individuals use space uniformly, and thus mix well spatially. In numerous species, however, individuals do not move randomly, but use spatial memory to visit renewable resource patches repeatedly. To understand the extent to which memory-based foraging movement may affect density-dependent population dynamics through its impact on competition, we developed a spatially explicit, individual-based movement model where reproduction and death are functions of foraging efficiency. We compared the dynamics of populations of with- and without-memory individuals. We showed that memory-based movement leads to a higher population size at equilibrium, to a higher depletion of the environment, to a marked discrepancy between the global (i.e. measured at the population level) and local (i.e. measured at the individual level) intensities of competition, and to a nonlinear density dependence. These results call for a deeper investigation of the impact of individual movement strategies and cognitive abilities on population dynamics.
大多数种群动态研究假设个体均匀地利用空间，因此在空间上很好地混合。然而，在许多物种中，个体并不是随机移动的，而是利用空间记忆反复访问可再生资源斑块。为了了解基于记忆的觅食运动通过其对竞争的影响而对密度依赖的种群动态的影响程度，我们开发了一个空间显式的、基于个体的运动模型，其中繁殖和死亡是觅食效率的函数。我们比较了有记忆和无记忆个体的种群动态。我们表明，基于记忆的运动导致平衡时的种群规模更高，对环境的消耗更大，全球（即在种群水平上测量）和局部（即在个体水平上测量）竞争强度之间存在明显差异，以及非线性密度依赖性。这些结果呼吁更深入地研究个体运动策略和认知能力对种群动态的影响。
