Well done to Pierre Lacoste and Riccardo Poloni who submitted their first manuscripts from their PhDs ! Both on polymophic Lepidoptera.
Lacoste et al. shows the results of mate choice experiments in the tropical butterfly Heliconius numata in French Guiana. They show an asymmetrical pattern of disassortative mating, with the morphs bearing the inversion allele displaying disassortative preferences, while the morph bearing the standard allele shows no preference. This contrasts with the pattern found in Peru, where disassortative mating was more or less symmetrical. Together with a simulations and analytical models, this leads to the prediction that mimetic benefits associated with the inversion is key to the stability of the polymorphism.
Thanks to Melanie McClure for cosupervising Pierre’s experiments in her lab in Cayenne, to Mathieu Chouteau for sharing experience and data, and to Ludovic Maisonneuve for his contribution to the modelling.
Lacoste P, Chouteau M, Maisonneuve L, Joron M* & McClure M* (submitted) « Asymmetry in disassortative mating sheds light on the processes maintaining inversion polymorphism ».
Poloni et al. reports the results of a predation experiment on the invasive box tree moth Cydalima perspectalis, using blue tits as predators. The papers shows that the white and dark morphs of this moth are under different predation regimes. The dark morph is cryptic and benefits from this especially when rare. The white morph is highly conspicuous and suffers more from predation, but benfits from a dilution effect when common, which is a rare finding for a highly palatable moth. Combined together the two forces may contribute to the maintenance of the polymorphism.
Thanks to Jonna Mappes and Ossi Nokelainen for their help and for hosting and training Riccardo and Marina at the Konnevesi research station in Jyvaskyla Finland.
Poloni R, Dhennin M, Mappes J*, Joron M* & Nokelainen O* (submitted) « Positive and negative frequency-dependent selection acting on polymorphism in a palatable moth ».
