PREMI

Aposematism is a widespread antipredator defence where prey advertise their chemical defence with warning signals. Previous work has demonstrated high within-species variation in how quickly predators learn to avoid aposematic prey, and this heterogeneity among predators is suggested to play an important role in the evolution of prey defences. This project aims to investigate what maintains the observed variation in predator behaviour by focusing on an unexplored mechanism: a predator’s gut microbiome. Evidence from humans and laboratory animals shows that gut microbiome can influence learning, memory and foraging choices (the microbiome-gut-brain axis), and theoretical models predict feedback loops between gut microbiome, diet and host behaviour. Here, I will translate this to the ecologically relevant context by 1) quantifying how the consumption of prey toxins alters the predator gut microbiome, physiology and foraging behaviour, 2) testing the effect of the early-life gut microbiome on foraging behaviour, and 3) determining the causal effect of the gut microbiome on foraging behaviour. I will use wild great tits (Parus major) as predators and combine several methods that include manipulating birds’ gut microbiome with prey toxins and faecal microbiota transplantation, quantifying gut microbial compositions from faecal samples using 16s rRNA sequencing, and conducting behavioural experiments to test avoidance learning, memory and dietary wariness. The results will address the current knowledge gaps in the predator-prey field by providing insights into the mechanisms that underly variation in predator behaviour. Furthermore, the project will advance our understanding of the ecological and evolutionary consequences of microbiomes for species dynamics. This will complement and broaden the current research of the host and enhance future career prospects of the applicant by providing an opportunity to gain new research skills and expand the fields of expertise.

2024

2026