Co-supervisor: Dr. A. Vanderpoorten (Liège univ., Belgium)
PhD project: Role of male sex pheromones in reproductive isolation and speciation in the African butterfly genus: Bicyclus (Kirby, 1871, Nymphalidae).
Evolution of reproductive isolation between diverging populations, i.e. speciation, is an essential process in Biology because it has generated the current species diversity. One main goal in evolutionary biology is to identify the phenotypic traits, and related genes, which generate or maintain reproductive isolation between populations and species. Olfactive signals, although ubiquitous in many organisms, are understudied compared to, for example, visual signals. However, olfactive communication plays a crucial role in mate attraction and mate choice and as such, it is potentially involved in reproductive isolation and speciation.
In Lepidoptera (butterflies and moths), sex pheromones have mainly been studied in females, nevertheless we know that males also produce pheromones. In the African butterfly Bicyclus anynana, it has been shown that male sex pheromones are involved in short-range courtship as the female chooses between males. We postulate that male sex pheromones could participate to reproductive isolation between species in Bicyclus butterflies, and could have played a role in generating the current species diversity of this group.
My main research lines are the following:
1. Field work in subsaharian Africa to collect as many of the 80 existing Bicyclus (sub)species as possible
2. Identification of the composition and of the chemical structure of the male sex pheromones in these Bicyclus species, using gas chromatography coupled to mass spectrometry.
3. Comparative phylogenetic approach of pheromone evolution: we expect that, if pheromones are involved in speciation, they should display a non neutral (non gradual) evolution in the Bicyclus phylogenetic tree, and differences in pheromone bouquets should be more important between sympatric species than between allopatric ones.
4. Behavioural approach: mate choice experiments with pheromone manipulation, and control of visual signals, will be performed to test the role of pheromones in maintaining current reproductive isolation between Bicyclus species.
5. Genetic approach: Identification of genes coding for enzymes involved in the pheromone biosynthetic pathway of B. anynana, based on what is known in female pheromone biosynthesis in moths.
This project benefits from the expertise of external collaborators:
- Prof. P. Brakefield and Dr. Patricia Beldade, Leiden university (the Netherlands)
- Dr. O. Brattström, Leiden university (the Netherlands)
- Miss M. de Jong, Leiden university (the Netherlands)
- Dr. H. Lei, Lund univ. (Sweden)
- Prof. C. Löfstedt, Lund university (Sweden)
- Dr. F. Molleman, Irvine University (USA)
- Prof. Antonia Monteiro, Yale university (USA)
- Dr. A. Vanderpoorten, Liège university (Belgium)
2008-2012 FRIA PhD student in the Académie Louvain
San Martin G, Bacquet P, Nieberding CM (2011) Mate choice and sexual selection in a model butterfly species, Bicyclus anymana : state of the art. Proc. Neth. Entomol. Soc. Meet. 22 : 9-22
| 25/11/2011 |