Pathways to survival in a hotter world

Introduction

Global warming and heatwaves are hallmarks of climate change that are expected to worsen in the 21st century. These phenomena diminish reproductive success and cause excess mortality in wild and domesticated animal populations. Yet, we still have sub-standard knowledge of almost all fundamental traits that mediate success or failure under climate change. For most animals, there are no data on the extent to which plasticity, local adaptation, or evolutionary change can alleviate the stress imposed by a hotter world. Collectively, therefore, the research field is at a status quo.

Objectives

To mitigate this situation, HotLife will leverage my previous phenomenological studies on ontogenetic priming and plasticity of thermoregulatory capacity to generate novel knowledge on when and why animals fail in the heat, and whether plastic or evolutionary responses may render failure a less likely outcome in the future.

Expected Outcomes

The main outcomes of HotLife will reveal:

1. How heat tolerance manifests, how much it can evolve, and whether plasticity halts evolutionary rescue.
2. Whether climate warming and climatic extremes directly or indirectly cut life expectancy short.
3. If the physiological basis for heat tolerance is inherited in the wild and if it is already being selected upon.

Methodology

I will achieve these ambitious goals by combining state-of-the-art thermal and sub-cellular physiology with intricate genomic techniques and powerful heritability analyses in captive and wild bird models—the endotherm group for which heat-induced mass mortality is most frequently reported.

Significance

HotLife goes beyond the state-of-the-art by: i. Bridging crucial knowledge gaps between heat failure in birds, its physiological basis, and its links to fitness and survival. ii. Addressing the potential for rescue by plasticity or evolution from these effects. iii. Uncovering evidence for local adaptation and heritability of heat tolerance in the wild.