Data from: Mating affects resource selection and modulates associational effects between neighbouring resources

Associational effects occur when the attack rate on a resource depends on neighbouring resources in the environment. These effects are predicted to result from mismatches experienced by the consumer organism in resource selection along hierarchical search levels. As resource selection depends on sensory information used during search behaviour, we expected that different physiological states of an insect might modulate the outcome of associational effects due to differences in resource selection. We used Drosophila melanogaster, as a model organism for olfactory-guided behaviour in insects, to study the effects of mating induced behavioural changes on associational effects between two alternative resources. We found that mating has no effect on the ability of D. melanogaster to locate resource patches, but rather affects the perception of the resources within the patch. Consequently, we only found associational effects in the experiments with unmated females and not in the experiments with mated females. Our results suggest that the lack of associational effects for mated females resulted from changes in the use of short-range olfactory cues, leading to random selection among the resources. In conclusion, our results suggest that the physiological state of an insect modulates associational effects by affecting resource selection rates within the patch.关联效应（Associational effects）指某一资源的攻击率取决于环境中邻近资源时所产生的生态学效应。此类效应被认为源于消费者生物在分级搜索层次上开展资源选择时所遭遇的匹配偏差。由于资源选择依赖于搜索行为过程中所利用的感官信息，我们推测昆虫的不同生理状态可通过改变资源选择模式，调节关联效应的最终结果。我们以黑腹果蝇（Drosophila melanogaster）作为昆虫嗅觉导向行为的模式生物，探究交配诱导的行为变化对两种替代资源间关联效应的影响。实验结果显示，交配状态并未影响黑腹果蝇定位资源斑块的能力，却会改变其对斑块内部资源的感知模式。据此，我们仅在未交配雌蝇的实验组中观测到关联效应，而交配雌蝇的实验组则未出现该效应。进一步分析表明，交配雌蝇未表现出关联效应的原因在于其对近距离嗅觉线索的利用方式发生了改变，最终导致其在不同资源间进行随机选择。综上，本研究结果证实，昆虫的生理状态可通过调控斑块内部的资源选择速率，对关联效应产生显著的调节作用。