Hypothesis
Adult queens touching pesticide residues in comb wax would suffer direct harm to their mass, sperm viability and reproductive performance, explaining links between wax residues and queen failure.
What failed
Six pesticides common in wax, alone and as a cocktail at 1–32 times typical wax concentrations, had no effect on queen mass, sperm viability or fat-body proteins in the lab. A field trial with the cocktail found no change in egg-laying pattern, queen mass, daughter-worker emergence mass or spermathecal proteins.
Broken assumption
Pesticide residues in wax harm queens through direct contact.
Why
The authors suggest earlier associations between wax residues and queen loss are more likely to arise indirectly, through effects on workers' care or perception of the queen.
From the published paper: McAfee et al. Scientific Reports, 2021. ↗CC BY