Department of Biology, Stanford University, Stanford, California, United States of America.
PLoS One. 2013 May 23;8(5):e63363. doi: 10.1371/journal.pone.0063363. Print 2013.
Collective behavior is produced by interactions among individuals. Differences among groups in individual response to interactions can lead to ecologically important variation among groups in collective behavior. Here we examine variation among colonies in the foraging behavior of the harvester ant, Pogonomyrmex barbatus. Previous work shows how colonies regulate foraging in response to food availability and desiccation costs: the rate at which outgoing foragers leave the nest depends on the rate at which foragers return with food. To examine how colonies vary in response to humidity and in foraging rate, we performed field experiments that manipulated forager return rate in 94 trials with 17 colonies over 3 years. We found that the effect of returning foragers on the rate of outgoing foragers increases with humidity. There are consistent differences among colonies in foraging activity that persist from year to year.
集体行为是由个体之间的相互作用产生的。个体对相互作用的反应差异会导致群体在集体行为方面产生重要的生态差异。在这里，我们研究了收获蚁 Pogonomyrmex barbatus 觅食行为在不同群体之间的变化。之前的研究表明，群体如何根据食物供应和干燥成本来调节觅食：外出觅食者离开巢穴的速度取决于带着食物返回的觅食者的速度。为了研究群体如何对湿度和觅食率做出反应，我们在 3 年内用 17 个群体进行了 94 次试验，人为地控制了觅食者的返回率。我们发现，返回觅食者对外出觅食者速度的影响随着湿度的增加而增加。不同群体之间的觅食活动存在一致的差异，且这种差异可以持续多年。
