Diversification of butterflies via male sex pheromones

ELIB

Researchers: Caroline Nieberding (principal investigator), Paul Bacquet (PhD student)
External collaborators:
- Prof. P. Brakefield, Dr. P. Beldade (Leiden univ., the Netherlands)
- Prof. K. Fischer (Greiswald univ., Germany)
- Prof. E. Hedenström (Sundsval univ. Sweden),
- Prof. C. Löfstedt (Lund univ., Sweden),
- Prof. A. Monteiro (Yale univ., USA)
- Dr A. Vanderpoorten (Liège univ., Belgium)

         

Sex pheromones are, from arthropods to mammals, essential chemical mediators of communication between males and females. As such they are potentially involved in adaptive evolution and reproductive isolation between species.
Our main question here is to test whether sexual selection on the production of male sex pheromones is responsible for reproductive isolation and species diversification in the butterfly genus Bicyclus.

         

This research program builds up on results from C. Nieberding’s postdoc and ongoing collaborative work with Prof. P. Brakefield. Male sex pheromones are known to be important in sexual selection in Bicyclus anynana. Moreover, the species-rich African butterfly genus Bicyclus is relevant for the questions we ask because the position and number of androconia, the male wing structures producing the pheromones, are major characters used for species discrimination in the genus. Therefore, we predict that sexual selection on pheromones, and their corresponding androconia, have participated to the diversification of this butterflies.We combine phylogenetic, behavioural and genetical approaches. Particularly, the analysis of the genetic bases of pheromone production in Bicyclus butterflies will benefit from several tools designed specifically for the laboratory model species B. anynana, such as microsatellites, BAC and EST libraries, quantitative PCR, transgenics, and high density gene arrays.

          
Using these tools, we aim to relate changes (mutations or variation in gene expression) in candidate genes involved in pheromone production to differences between the pheromones of different Bicyclus species and populations and link the changes to their diversification history. This will allow associating the phenotypic variation in pheromone production with the genetic bases generating this variability and the consequences of this variability on reproductive isolation.