Islands as natural laboratories of global warming: discovering insects’ ability to survive thermal extremes

Introduction

Global warming will increase the frequency of extreme heat events, exemplified by this year’s European heatwave. These thermal extremes pose challenges to insects, who play an indispensable role in terrestrial ecosystems, and whose body temperatures rise with habitat temperatures. Given the alarming trend of global insect declines, it is essential to understand their adaptability in the face of rising temperatures. IGNITE aims to answer one of the most urgent questions in ecology today—Will insects be able to survive the upcoming heat stress?

Research Approach

To answer this question, we will test insects’ resilience to thermal extremes using an interdisciplinary approach that integrates insect physiological and behavioral responses with relevant micro- and macro-climates.

Microclimatic Insights

Using state-of-the-art 3D thermal imaging of the habitat, we will determine how microclimatic heterogeneity combined with insect behavioral thermoregulation governs insect survival to extreme heat. While such microclimatic insights are pivotal, predicting long-term changes requires a macroclimatic perspective.

Macroclimatic Modeling

Thus, we will develop a high-resolution climatic model of surface temperatures to forecast heatwave frequency and intensity on Mediterranean islands.

Experimental Design

We will test insects’ thermal plasticity potential with novel reciprocal transplant experiments in both the field and laboratory. We will use ants as model insects, due to their global distribution and ecological importance.

Focus on Ants

Under temperature extremes projected by the macroclimatic model, we will determine ant thermal plasticity and its ramifications on ecosystem functions such as:

1. Seed dispersal
2. Plant productivity
3. Biodiversity

Integration of Disciplines

IGNITE integrates findings from climatology, behavioral ecology, and ecophysiology to understand insect resilience to temperature increases and cascading effects on ecosystems. By doing so, it will pioneer global change biology research in the Mediterranean Region using islands as natural laboratories to study global warming.