Seminal fluid compromises visual perception in honeybee queens reducing their survival during additional mating flights

Queens of social insects make all mate-choice decisions on a single day, except in honeybees whose queens can conduct mating flights for several days even when already inseminated by a number of drones. Honeybees therefore appear to have a unique, evolutionarily derived form of sexual conflict: a queen's decision to pursue risky additional mating flights is driven by later-life fitness gains from genetically more diverse worker-offspring but reduces paternity shares of the drones she already mated with. We used artificial insemination, RNA-sequencing and electroretinography to show that seminal fluid induces a decline in queen vision by perturbing the phototransduction pathway within 24-48 hours. Follow up field trials revealed that queens receiving seminal fluid flew two days earlier than sister queens inseminated with saline, and failed more often to return. These findings are consistent with seminal fluid components manipulating queen eyesight to reduce queen promiscuity across mating flights. Overall design: Two subsequent RNA-seq experiments, each with three treatment groups. Each treatment consisted of three biological replicates. Each biological replicate was a pool of three brains of honeybee queens after they were artificially inseminated with either semen, seminal fluid or mock-inseminated (first experiment), or semen, seminal fluid and Hayes saline (second experiment). RNA-seq libraries were sequenced on Illumina HiSeq 2500 (single-end 120 bp reads).