The role of the gut microbiome in host responses to environmental variation: within and across generations and species

Introduction

The gut microbiome is strongly linked to health and sickness. A current key challenge is to understand how the microbiome helps the host adapt to environmental variation. Yet, most research originates from few laboratory animal models and thus misses large parts of environmental, physiological, and life-history variation, while data from wild populations and species is needed.

Aim of the Study

Our overarching aim is to unravel how the microbiome mediates the host’s responses to environmental variation, covering molecular to evolutionary scales, using wild birds as a study system. We focus on how the gut microbiome helps hosts cope with temperature variation, given the pervasiveness of temperature as a challenge across taxa, and climate-crisis driven thermal challenges.

Objectives

1. (O1) To study the role of the microbiome in mediating host (adaptive) reversible thermal plasticity in adulthood.
2. (O2) To assess the role of the microbiome in mediating host (adaptive) developmental and transgenerational thermal plasticity, and explore the underlying epigenetic changes.
3. (O3) To quantify the contribution of host genetic variation and the microbiome on host thermal physiology.
4. (O4) To explore the macroevolutionary patterns of microbiome and host thermal physiology.
5. (O5) To examine the underlying molecular mediators of host-microbiome interactions.

Methodology

To understand the causal role of the microbiome, we apply state-of-the-art methods (including microbiome transplants) within and across populations (O1) and generations (O2). We identify the molecular mediators (including bacterial vesicles; O5), using many tools adapted from the biomedical field to eco-evo research.

Innovative Approaches

We further use quantitative genetics, reaction norms, selection lines (O3), and multivariate phylogenetic models (O4), which are rarely used in the host-microbiome field, opening new lines of research.

Expected Outcomes

We aim to produce groundbreaking findings on the microbiome-mediated mechanisms of phenotypic variation, which will help to predict how organisms respond to anthropogenic changes.