Effects of global climate change of the Brazilian fauna: a conservation physiology approach

Abstract

An unequivocal pattern that involves both natural and entropic causes is the global, yet heterogeneous, change in the climate of earth. Although this trend is expected to cause pervasive effects on the BIOTA, the nature, span and final consequences of climate change must differ among tax, even among animal species, because of the vast diversity in physiological traits and ecological associations evident in the fauna. Understanding the nature of differential effects of climate change on animal species is one of the many urgent and interdisciplinary challenges faced by contemporary science, and enhancing this understanding is the main general goal of this project. We propose an integrative ecophysiological and comparative approach that is derived from the conceptual framework supporting the emerging discipline known as conservation physiology. A main tenet of this discipline is that populations exposed to environmental change may crash when most individuals deteriorate, and that individuals decline when they reach a physiological state that prevents them to maintain proper internal equilibrium through time. It follows that the effects of climate change on animal species cannot be assessed from the type, magnitude or time scale of the perturbation, but from the physiological states caused by it; and that the same pattern may be deleterious for one species and innocuous to another. We ask how and why physical variables related to climate induce noxious physiological states in some animal species and not in others, what are the limits and paths of physiological adjustment to climate, how early stages of life cycles are affected by climatic variables, and what are the energetic costs and trade-offs imposed on animals by climate shifts. These general questions are tackled using key models carefully selected from the Brazilian fauna, not only because they represent diverse metabolic and ecological profiles, but also because of apparent sensitivity. (AU)