Cognitive scores of bees exposed to various environmental stressors

Environmental stressors have sublethal consequences on animals, often affecting the mean of phenotypic traits in populations. However, effects on inter-individual variability are poorly understood. Since phenotypic variability is the basis for adaptation, any change due to stressors may have important implications for population resilience. 
Here we explored this possibility in bees by analysing raw datasets from 23 studies (5,618 bees) in which individuals were first exposed to stressors and then tested for cognitive tasks.
While all types of stressors decreased the mean cognitive performance of bees, they increased cognitive variability. Focusing on 14 pesticide studies, we found that the mode of exposure to stressors and the dose were critical. Mean cognitive performance was more affected by a chronic exposure than by an acute exposure. Yet, cognitive variability increased with increasing doses following both exposure durations.
Policy implications: Current guidelines for the authori..., Search and selection of datasets
The search for datasets in scientific publications falling within the scope of our research question was performed in July 2020 using the PubMed database. The words used for the search were (“Stressor” OR “Pesticide” OR “Parasite”) AND (“Cognition” OR “Learning”) AND (“Bees”). This search was not restricted to any section of the manuscripts and automatically extended to similar terms intended under the MeSH hierarchy of the database. A total of 240 studies were found, of which 18 met our inclusion criteria regarding the cognitive task and the type of stressor (see below). The search terms under which each study was found are available in the Supplementary Table 1. Five datasets belonging to the authors of this study were also included as they filled the inclusion criteria. These studies measured the impact of stressors on the cognitive performance of bees. The list of the 23 selected studies is available in Table 1.
Cognitive tasks: We focused on cogniti..., Files can be opened using any text editor.