Ms Isabelle Létourneau
|iletourn [at] connect [dot] carleton [dot] ca|
|Telephone||+1 613 520 2600 (ext. 3866)|
|Fax||+1 613 520 3539|
I am increasingly interested in the evolution of senescence and the hypotheses that have been posited to explain why organisms can’t maintain indefinitely what is already formed. My research aims to elucidate the nature of maintenance-reproduction trade-offs which underpin the “disposable soma” hypothesis for senescence.
Traits favouring somatic maintenance may only be selected at the expense of reduction in the overall rate of reproduction and vice versa. Thus, investing resources into a longer lifespan should only occur until it is no longer advantageous for the reproductive success. Monarchs (Danaus plexippus) are known to exhibit extreme inter-population variation in longevity dependent on migratory strategy making them excellent candidates for testing life-history theories of senescence. It has been suggested that the number of times female Monarchs engage in reproduction has no effect on lifespan. However, laboratory settings often exhibit environments which are benign and where resource intake, more commonly known as DR (diet restriction) is not fully accounted for. To understand the patterns of trade-offs in life history theory, we must control for different levels of resource scarcity.
Recent research on Drosophila sp. has tip-toed around this problem, never truly calibrating the intake of each specimen. Diluted diets could be compensated by eating more of these diets! Other studies have invoked a phenotypic component of protein: carbohydrate individual choice to their experimental design with interesting results. My goals are to find a way to calibrate exact diet amounts for experimental groups with different levels of reproduction events to see their concerted effects on lifespan.
I am an amateur lepidopterist and butterfly taxonomist. I like to participate in local butterfly counts. On my free time, I go out on the field to assess local species richness and assemblages. I am also interested in insects and other arthropods in general such as Hymenoptera, Diptera and Araneae.
Létourneau, I.S., M. Larrivée and A. Morin (In review) A comparative analysis of butterfly richness detection capacity of Pollard transects and general microhabitat surveys. The Canadian Entomologist.