Gordon Deborah M
Department of Biological Sciences, Stanford University, Stanford, California 94305-5020, USA.
Am Nat. 2002 May;159(5):509-18. doi: 10.1086/339461.
Behavioral plasticity in social insects is intriguing because colonies adjust to environmental change through the aggregated responses of individuals. Without central control, colonies adjust numbers of workers allocated to various tasks. Individual decisions are based on local information from the environment and other workers. This study examines how colonies of the seed-eating ant Pogonomyrmex barbatus adjust the intensity of foraging in an arid environment where conspecific neighbors compete for foraging area. The main question is how foragers decide whether to leave the nest. Patrollers search the area before foragers emerge. Removal experiments show that the return of the patrollers stimulates the onset of foraging, and later, the rate at which foragers return affects the rate at which foragers continue to leave the nest. Foraging activity is less sensitive to changes in the rate of returning foragers than to changes in the rate of returning patrollers. These results suggest that whether a colony forages at all on a given day depends on conditions detected early by patrollers but that once foraging begins, the intensity of foraging does not track, on an hourly timescale, how quickly foragers can find food.
群居昆虫的行为可塑性很有趣，因为蚁群通过个体的聚集反应来适应环境变化。在没有中央控制的情况下，蚁群会调整分配到各项任务的工蚁数量。个体的决策基于来自环境和其他工蚁的局部信息。本研究考察了以种子为食的巴氏收获蚁（Pogonomyrmex barbatus）蚁群在干旱环境中如何调整觅食强度，在这种环境中，同种邻居会争夺觅食区域。主要问题是觅食者如何决定是否离开巢穴。巡逻蚁在觅食者出现之前搜索区域。移除实验表明，巡逻蚁的返回会刺激觅食行为的开始，随后，觅食者返回的速率会影响觅食者继续离开巢穴的速率。觅食活动对觅食者返回速率变化的敏感度低于对巡逻蚁返回速率变化的敏感度。这些结果表明，一个蚁群在某一天是否觅食取决于巡逻蚁早期检测到的情况，但一旦觅食开始，在每小时的时间尺度上，觅食强度并不跟踪觅食者找到食物的速度。
