Data from: Under the influence: sublethal exposure to an insecticide affects personality expression in a jumping spider

1. Consistent behavioural differences between individuals have far-reaching implications for ecology and evolution, including how populations cope with increasing anthropogenic changes, notably pesticides. Although sublethal doses of insecticides are known to alter behaviour, current studies on the relationship between toxicants and behaviour tend to ignore effects on individual variation.
2. Our objective was to determine whether sublethal exposure to an organophosphate insecticide could affect the consistency of individual behaviour and disrupt behavioural correlations, in a jumping spider occurring in agroecosystems. Adults of the jumping spider Eris militaris (Araneae: Salticidae) were scored by an open-field and a prey-capture assay, each conducted as pre- and post-insecticidal exposure to the organophosphate phosmet. Half of the individuals received no exposure to the insecticide to provide a control group. We then estimated the changes in repeatability, a measure of the extent of personality differences, and in behavioural correlations between control and insecticide-treated groups.
3. Although insecticide exposure had no discernable effects on the population’s average behaviours, insecticide-exposed individuals showed an average of 23 % lower repeatability and the correlation between activity and prey capture was more strongly collapsed in females.
4. Our results provide clear evidence that exposure to sublethal doses of insecticides on an important arthropod predator in agroecosystems causes substantial alteration of personality differences even in absence of a population-wide shift in behaviour. This suggests insecticide effects are more complex than previously thought and indicates high variation in the way individuals coped with insecticidal exposure.
5. By altering the consistency of behavioural traits and their correlations, exposure to sublethal concentrations of insecticides can have subtle effects on behavioural expression, which may ultimately affect biocontrol performance in an important arthropod predator in agroecosystems. Our study calls for an increasing focus on individual behavioural variation when testing the effects of pesticides on non-targeted fauna.

1. 个体间稳定的行为差异对生态学与进化研究具有深远意义，涉及种群如何应对日益加剧的人为环境变化，尤其是农药胁迫。尽管已知亚致死剂量的杀虫剂会改变动物行为，但当前有关有毒物质与行为间关联的研究往往忽略了其对个体行为变异的影响。
2. 本研究旨在明确暴露于有机磷杀虫剂（organophosphate insecticide）是否会影响个体行为的一致性，并破坏行为相关性，研究对象为栖息于农业生态系统中的跳蛛（jumping spider）。我们针对铜草跳蛛（Eris militaris，蜘蛛目Araneae：跳蛛科Salticidae）成蛛，分别在暴露于有机磷杀虫剂亚胺硫磷（phosmet）前后，通过开阔场行为试验（open-field assay）与捕食捕获行为测定（prey-capture assay）对其行为进行评分。设置半数个体不接触杀虫剂，作为对照组。随后我们评估了对照组与杀虫剂处理组的个体行为重复性（repeatability，即衡量个体个性差异程度的指标）以及行为相关性的变化。
3. 尽管杀虫剂暴露对种群的平均行为无显著影响，但暴露于杀虫剂的个体平均行为重复性降低了23%，且雌性个体的活动能力与捕食行为间的相关性显著减弱。
4. 本研究结果清晰证明，农业生态系统中的重要节肢动物捕食者（arthropod predator）暴露于亚致死剂量杀虫剂后，即便种群整体行为未发生整体偏移，其个体行为个性差异仍发生了显著改变。这表明杀虫剂的影响比此前预想的更为复杂，同时也反映出个体应对杀虫剂暴露的方式存在高度变异。
5. 亚致死浓度的杀虫剂暴露会通过改变行为性状的一致性及其相关性，对行为表达产生微妙影响，这最终可能影响农业生态系统中重要节肢动物捕食者的生物防治（biocontrol）效能。本研究呼吁在评估农药对非靶标动物群的影响时，应愈发关注个体行为变异。