Overview and general interests

I am fascinated by enemy-victim interactions. My research addresses how these interactions change in response to the ecological and evolutionary contexts in which they are immersed. I am particularly interested in how predators and competitors modify the expression of host defence against parasites, either directly through their effects on defense or indirectly via effects on correlated traits. 
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To this end I use a combination of experimental evolution, laboratory assays, field surveys and mathematical modelling.

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Evolution of defence under relaxed selection

Despite instances where a source of selection is removed or decreased (i.e. relaxed selection) being common, most of our understanding of evolution is built on cases where a new source of selection emerges or a previously present one increases. My research addresses how various components of host defence (e.g. resistance and tolerance) evolve under relaxed selection in natural environments, where interactions with co-existing species – beyond the host-parasite pair dynamic- can influence the evolutionary trajectories of traits.

Relevant papers: Dargent et al. 2013 PRSB; Dargent et al. 2014 PRSB; Dargent et al. 1016 JEB; Gotanda et al. 2013 Oecologia

Sex-biased parasitism

Sex-biased parasitism, the condition under which one sex carries on average higher parasite loads, is a common occurrence in nature with potentially major implications for disease dynamics and defence evolution. Yet, the main causes of this pattern continue to be the center of debate. My research addresses the ecological, physiological and evolutionary drivers of sex biased parasitism. In particular I assess how sex differences in defence affect the evolution of resistance and tolerance; and the effects of sexual dimorphism and androgen expression on anti-parasite defence. 

​Relevant papers: Dargent et al. 1016 JEB; Dargent et al. 2015 Parasitology; Dargent & Forbes 2015 IEE  

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Disease-diversity relationships

We live in a context of unprecedented biodiversity loss and emergent infectious diseases. My research explores the links between these two processes, addressing whether and how changes in species diversity influence the spread of disease (dilution/amplification effects). In particular I explore the effects of social manipulation of diversity (heterospecific associations) on infection; the effects of parasite interactions and infracommunity diversity on parasite abundance; and the relative importance of host and parasite traits on the outcome of disease-diversity relationships.


Relevant papers: Dargent et al. 2017 IJP-PAW; Morril, Dargent & Forbes 2017 IJP; Dargent & Forbes 2015 IEE; Dargent et al. 2013 PLOS ONE