Physiological ecology meets climate change

Abstract

In this article, we pointed out that understanding the physiology of differential climate change effects on organisms is one of the many urgent challenges faced in ecology and evolutionary biology. We explore how physiological ecology can contribute to a holistic view of climate change impacts on organisms and ecosystems and their evolutionary responses. We suggest that theoretical and experimental efforts not only need to improve our understanding of thermal limits to organisms, but also to consider multiple stressors both on land and in the oceans. As an example, we discuss recent efforts to understand the effects of various global change drivers on aquatic ectotherms in the field that led to the development of the concept of oxygen and capacity limited thermal tolerance (OCLTT) as a framework integrating various drivers and linking organisational levels from ecosystem to organism, tissue, cell, and molecules. We suggest seven core objectives of a comprehensive research program comprising the interplay among physiological, ecological, and evolutionary approaches for both aquatic and terrestrial organisms. While studies of individual aspects are already underway in many laboratories worldwide, integration of these findings into conceptual frameworks is needed not only within one organism group such as animals but also across organism domains such as Archaea, Bacteria, and Eukarya. Indeed, development of unifying concepts is relevant for interpreting existing and future findings in a coherent way and for projecting the future ecological and evolutionary effects of climate change on functional biodiversity. We also suggest that OCLTT may in the end and from an evolutionary point of view, be able to explain the limited thermal tolerance of metazoans when compared to other organisms.

Stage-specific heat effects: timing and duration of heat waves alter demographic rates of a global insect pest

“…Furthermore, due to inter-annual variation in the timing and duration of hot days, heat events may affect a single life-stage or multiple life-stages, with the stages affected varying among years. Despite recent progress in this field (Bowler and Terblanche 2008;Kingsolver et al 2011;Bozinovic and Portner 2015), it remains unclear how this variation in the stage-specific timing of hot events affects key demographic rates of organisms.…”

The sea urchin Lytechinus variegatus lives close to the upper thermal limit for early development in a tropical lagoon

“…Such prediction requires a comprehensive understanding of vulnerability to thermal stress that can be generalized across regions, habitats, taxa, and life history stages (Munday et al. 2013; Bozinovic and Pörtner 2015; Polgar et al. 2015).…”

A global review of freshwater crayfish temperature tolerance, preference, and optimal growth

“…This approach used a biochemical measure of metabolic activity based on oxygen consumption by enzymes and represents a rapid and non-lethal alternative to traditional temperature tolerance approaches (Simčič et al 2014). Another physiologically-based approach that has gained popularity, especially for marine fishes, is the oxygen-and capacity-limited thermal tolerance (OCLTT) methodology (Pörtner 2010;Bozinovic and Pörtner 2015). This approach is based on the hypothesis that fitness is highly correlated to delivery of oxygen to tissues and aerobic performance (Pörtner 2010).…”