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Lecureuil, C.

Publications and source records attributed to Lecureuil, C..

2 recordsLinked to original sources

Deltamethrin-induced neurotoxicity: A stage-specific analysis of the European earwig head proteome

Pesticides are ubiquitous in agroecosystems and pose substantial risks to non-target organisms. Traditional ecotoxicological assessments focus on survival, reproduction, or overt behavior, yet these endpoints may fail to detect subtle, molecular-level stress. Here, we investigated the effects of sublethal deltamethrin exposure on the head proteome of field-collected European earwig (Forficula auricularia) females, sampled at two life stages (pre-oviposition and post-family life) to account for physiological context. Our results reveal that deltamethrin induces a robust proteomic response shared across developmental stages, including the regulation of key detoxification enzymes (NADPH- cytochrome P450 reductase, arginine kinase). In parallel, stage-specific responses were observed, involving proteins related to metabolism, stress response, and cellular organization. Strikingly, these molecular perturbations occurred without detectable changes in reproductive traits, highlighting a disconnect between cellular stress and organismal phenotypes. Several uncharacterized proteins were consistently regulated, representing promising targets for future studies on pesticide adaptation and potential detoxification pathways. Overall, these findings suggest that classical phenotypic assays may underestimate sublethal pesticide effects, and that proteomic profiling provides a sensitive framework to uncover underlying molecular responses. By integrating natural variability, realistic exposure, and reproductive physiology, our study emphasizes the need for molecular approaches in environmental risk assessment and offers a new perspective on the subtle, cryptic effects of agrochemicals.

ecology↗

Relationship between weapon size and six key behavioural and physiological traits in males of the European earwig

In many animals, male weapons are large and extravagant morphological structures that typically enhance fighting ability and reproductive success. It is generally assumed that growing and carrying large weapons is costly, thus only males in the best condition can afford it. In the European earwig, males carry weapons in the form of forceps-like cerci, which can vary widely in size within populations. While long forceps appear to increase males access to females, it is unknown whether it also correlates with other important male lifen-history traits. This information is important, however, in determining the potential reliability of forceps length as an indicator of male quality and the stability of this signalling system. Here, we tested whether forceps length is associated with six important behavioural and physiological traits in males of the European earwig. We sampled hundreds of males from two populations, selected 60 males with the longest and shortest forceps from each population, and then measured locomotor performance, boldness, aggregation behaviour, survival under harsh conditions, sperm storage, and survival after pathogen exposure. Contrary to our predictions, we detected no main association between forceps length and the traits measured. This lack of association was consistent between the two populations, although there were population-specific levels of boldness, aggregation and survival in harsh conditions (for long-forceps males only). Overall, these results challenge our current understanding of the function and quality signal of forceps length in this species and raise questions about the evolutionary drivers that could explain the maintenance of weapon size diversity within and between populations.

evolutionary biology↗