Current Research project
Uncovering the evolutionary history of the Colorado potato beetle
The Colorado potato beetle (Leptinotarsa decemlineata, Say; CPB) is a major pest of potato crops. Thought to originate from Mexico (where most of the Leptinotarsa diversity is found), it was discovered in central U.S. in the early 19th century and quickly invaded potato crops, rapidly expanding its distribution towards the East coast. It is now distributed worldwide in the Northern hemisphere and is still spreading northward.
Along with his notable capacity of adapting to high latitudes, the Colorado potato beetle has evolved resistance to any pesticide that have been used against him. It is now resistant to 54 different compounds, encompassing most modes of action, making it one of the most successful superpest species. Interestingly, resistance patterns are heterogenous, with sympatric populations exhibiting both low and high levels of tolerance to specific pesticides, offering good opportunities to quantify adaptive processes at the genome level.
I am interested in understanding the mechanisms and processes by which the Colorado potato beetle can exhibit such rapid rate of evolution. To do so, I am taking advantage of re-sequenced whole genomes of CPB, sampled throughout U.S., but also in Mexico and Europe, along with some closely-related Leptinotarsa genomes. I am currently investigating the geographic origin of CPB, U.S. populations structure, relationships and demographic history. I am also uncovering specific, among-populations adaptive patterns by detecting genome-wide signatures of selection and relating them to known genes, traits and agents of selection.
Previous research projects
Phylogeny of the Tetrapus genus
(pollinators of the Pharmacocysea section of fig trees)
Phenotypic plasticity and phase polyphenism in the Desert locust
Quantifying sexual selection in hermaphrodites
Ecological speciation in the European corn borer, Ostrinia nubilalis