Baptiste Nézel
Research interest:
I am mainly interested in the ant universe. I have always been impressed by the complexity of the behaviour and ecology of those eusocial insects. From their biology to the tight interactions they entertain with species from all the different reigns (plants, fungi and animals), they represent endless source of biological models from which a lot remains to be understood.
Current Project: EMINENT - Consequences of an EMerging parasite on an INvasive aNT species in Europe
My current project focuses on the interaction between Laboulbenia formicarum, an ectoparasite fungus, and its host, the invasive garden ant Lasius neglectus. Recent studies have shown that the fungal infection level in the French populations of ants is increasing extremely rapidly (Tragust et al. 2015 ).
Based on existing prevalence information on the distribution of this parasitic interaction in the surrounding area of Lyon, France (Gippet et al., 2021 ), I will try to understand the effects of Lab. formicarum on Lasius neglectus, from the direct fitness impact to the changes in ant behaviour due to infection. In addition, I would like to check whether there are modifications at the community level and see if there are differences in ant species richness and evenness around L. neglectus’ nests. Later, I would like to see whether a spillover is possible from the invasive species to the native ones.
Ongoing work:
Fitness Experiment:
Right now, I'm looking into how Laboulbenia formicarum might affect the fitness of Lasius neglectus by checking out the nest performance in terms of brood production. To do this, I set up 52 tiny colonies in mini nests, which took quite a lot of time to prepare. The colonies are made up of two queens and 200 (±25) workers, taken from the live samples I brought back from France (see below for fieldwork description). The ants are fed twice a week, and I count the number of dead individuals at the same time (thanks to Hannah for the help). Finally, every two weeks, I also total the brood number, including all eggs, larvae and pupae which take a huge amount of time...
Aggression and nestmate recognition experiment:
Hannah is working on a BSc thesis project that looks at how tje fungal infection might affect the competitive abilities of the invasive ant. This involves looking at how aggression towards other ants (both infected and uninfected) and towards native ant species such as the black garden ant (Lasius niger) varies. At the same time, she is assessing cuticular hydrocarbons profiles to see if Lab. formicarum is affecting them, to see if our biological system works like the one made of the Laboulbeniale Rickia wasmannii and the ant Myrmica scabrinodis (Csata et al., 2023 ).
Completed work:
Fieldwork:
From 27 March to 1 June, I had the opportunity to embark on an excursion to Lyon and its surrounding areas with the aim of collecting ants. Based on the previous data gathered by Gippet et al. (2021) , I attempted to observe the evolution of the area covered by different supercolonies of Lasius neglectus with the invaluable assistance of Hannah Gaitzsch and Nina Schäffner. At the same time, we also screened the infection prevalence on those supercolonies, as well as the possible variation in the ant community around the same supercolonies. In other words, we went digging in the mud, we flipped all the stones and wood logs around, and we spent lovely rainy days under the microscope identifying those ants. We would also like to express our gratitude to Dr. Bernard Kaufmann from the lab LEHNA of the University Claude Bernard Lyon 1 for welcoming us there!
Previous experiences:
I did my Master thesis on the population genetic of the black garden Lasius niger, at the University of Bern, with Dr. Alexis Beaurepaire. There I aimed to evaluate whether it was possible to distinguish these ant’s populations on a continental scale, using neutral DNA markers.