Invasion Hologenomics

Human-mediated introductions of invasive alien species (IAS) have been recognised as one of the major threats to biodiversity and ecosystem functioning, due to the many impacts and rapid spread of IAS. However, the mechanisms underlying invasiveness have not been fully disclosed yet. We hypothesise that metagenomic plasticity may be involved in the invasion process, conferring IAS the capability to quickly adapt to their new environment and out-compete native species. To test this hypothesis, we will study gut microbiome dynamics in two phylogenetically-close mammals: a successful invader (grey squirrel, Sciurus carolinensis) and a native species ousted by the former (red squirrel, Sciurus vulgaris). We will also investigate the diverse interplay among their gut microbiome and key phenomic traits like dietary flexibility, behaviour (individual personality) and resistance to parasitic infection. We will employ an observational approach in a natural experimental setting, comparing variation in the microbiome-phenome dynamics of the two species at both the individual-level (across seasons) and population-level (along a natural-urban gradient). By helping to disclose the mechanisms behind invasiveness and rapid adaptation of IAS, this project will offer new insights that may prove relevant for the prevention and management of biological invasions.