How beetle moms tell mates to bug off

Caring for newborns is tough for all kinds of new parents. The burying beetles Nicrophorus vespilloides, for example, have to juggle their responsibility of feeding carrion to hungry larvae and their drive to make more offspring. Tending to existing young, rather than making new ones, is the more successful strategy for this beetle. Now, researchers led by Sandra Steiger of the University of Ulm have discovered that the female N. vespilloides manages this balancing act by being infertile in her brood’s early days. What’s more, the scientists found females give off a volatile compound that lets males know nothing will come from efforts to copulate (Nat. Commun. 2016, DOI: 10.1038/ncomms11035). By using deuterium labeling, the researchers learned that the hormone that makes the female infertile and the antiaphrodisiac pheromone—methyl geranate—arise from the same biosynthetic precursor. “There can be intense conflicts between males and females over mating rate or how much each sex should invest in raising the young,” the authors note. “Our results uncover mechanisms underlying parental care decisions, and illustrate how a physiological interplay between hormone and pheromone systems guarantees that both parents draw their attention towards the existing young as long as they are needy.”