An experimental test of the role of environmental temperature variability on ectotherm molecular, physiological and life-history traits: implications for global warming

FOLGUERA, G,; BASTÍAS, D. A.; CAERS, J.; ROJAS, J. M.; PIULACHS, M-D; BELLÉS, X ; BOZINOVIC, F.

COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. A: COMPARATIVE PHYSIOLOGY.

Elsevier

Lugar: Amsterdam; Año: 2011 vol. 159 p. 242 - 246

0300-9629

Global climate change is one of the greatest threats to biodiversity; one of the most important effects is the 25 increase in the mean earth surface temperature. However, another but poorly studied main characteristic of 26 global change appears to be an increase in temperature variability. Most of the current analyses of global 27 change have focused on mean values, paying less attention to the role of the fluctuations of environmental 28 variables. We experimentally tested the effects of environmental temperature variability on characteristics 29 associated to the fitness (body mass balance, growth rate, and survival), metabolic rate (VCO2) and molecular 30 traits (heat shock protein expression, Hsp70), in an ectotherm, the terrestrial woodlouse Porcellio laevis. Our 31 general hypotheses are that higher values of thermal amplitude may directly affect life-history traits, 32 increasing metabolic cost and stress responses. At first, results supported our hypotheses showing a diversity 33 of responses among characters to the experimental thermal treatments. We emphasize that knowledge about 34 the cellular and physiological mechanisms by which animals cope with environmental changes is essential to 35 understand the impact of mean climatic change and variability. Also, we consider that the studies that only 36 incorporate only mean temperatures to predict the life-history, ecological and evolutionary impact of global 37 temperature changes present important problems to predict the diversity of responses of the organism. This is 38 because the analysis ignores the complexity and details of the molecular and physiological processes by which 39 animals cope with environmental variability, as well as the life-history and demographic consequences of 40 such variability.