My main field of research is the ecological immunology of arthropods. It focuses on the factors (biotic and abiotic) that shape immune defense strategies in invertebrates; and, particularly, the causes and consequences of variation in immunity within and between species.
During my PhD, I investigated how immune system of herbivores is modulated by both host plants and natural enemies. I examined, for the 1st time, the effect on larvae immune pathways (constitutive and induced) of various host plant varieties and artificial diets containing host plants. Here, herbivores invest differently in immune pathways depending on the host plant on which they fed. I also found that local parasite pressure can shape immune investment. Finally, I investigated the investment in different types of defenses (behavioral, morphological and immunological defenses) of two related moth species. This experiment combined experimental factors, elucidating the evolution of herbivore defense strategies and population regulation. Excitingly, these findings also show a strong potential for practical application in pest management.
As a postdoc at the French National Institute for Agricultural Research (INRA), I lead as well as executed a comprehensive investigation into the regulation and resistance of arthropod populations and leaf diseases in vineyards in response to anthropic (i.e. management practices in crops) and non-anthropic (e.g. rainfall and vine phenology) disturbances. This study was very novel in that it explored both arthropod and disease simultaneously – a rarity within this field. This study uncovered yielded crucial insights into community regulation and the interaction between host plants, leaf diseases, and leaf arthropods.
As a postdoc at the University of Mainz, I sought to expand my knowledge in defensive strategies by exploring social immunity provided by parents in sub-social species (i.e. earwigs) and by group members in eusocial species (i.e. ants and bees). I have obtained all funding for this multi-faceted project, and was designed and lead by myself. While this project is still in progress for the eusocial portion, I have already found, in sub-social species, that maternal presence did not affect offspring immunity in the short- or the long-term, even when offspring were exposed to pathogens. Surprisingly, maternal presence appears to generally reduce offspring survival in this system. These results are highly important for better understanding the evolution of parental care in insects, and reveals that the benefits of family interactions – in terms of protection against pathogen infection – are unlikely to be driven by the mother.
Since 2009, I have acquired a strong background in the different mechanisms of defenses in insects. I adapted and developed proxies to measure investment in immunity across a number of individual taxa (Coleoptera, Dermaptera, Hymenoptera and Lepidoptera). Using different methods, such as microbiology and spectrophotometry, I was able to obtain a clear idea of the investment of insect in immunity (Vogelweith et al., 2011; Vogelweith et al., 2013; Vogelweith et al. 2017). I also developed methods and tools to measure insect investment in behavioral and morphological defenses (Vogelweith et al., 2014). I learned to measure investment in chemical defenses using High-Performance Liquid Chromatography coupled with Mass Spectrometry (HPLC-MS). Finally, I am currently working on a genomic method using transcriptomic analyses to better understand the molecular mechanisms underlying immune regulation and immune gene expression. All these methods together will allow me to have now a more complete picture of insect investment in defensive mechanisms using a very diversified but complementary toolbox, including chemical, analytical, behavioral, morphological, physiological, and molecular approaches. All these tools are key components which can be integrated into a wider theoretical framework in order to better understand several ecological and evolutionary processes.