The impact of social interactions on thermoregulation and habitat use in lizards: analyzing the role of behavioral syndromes in changing environments

Abstract

Physiological and behavioral mechanisms allow ectotherms to maintain their body temperature (Tb) within an optimal thermal range (Tset-range). Associated costs such as low availability of suitable thermal spots, environmental temperatures (Ta) that exceed the lower and upper Tset or the interaction with other organisms that share the same micro-habitat may impinge on these mechanisms affecting the performance of the individuals and eventually the fitness of the species. Depending on particular behavioral characteristics, organisms will be more or less capable or stimulated to surpass obstacles or barriers that prevent thermoregulation. Throughout this research we aim to explore the role of social interactions and individual variation on behavioral syndromes associated with thermoregulation and habitat use in lizards. We will register social and thermoregulatory behaviors in different community assemblages that will be manipulated by combining one to three species in semi-natural enclosures. We propose that behaviors and the corresponding responses may vary among and within species and such variation can strongly impact species adjustments in changing scenarios or novel environments. We will quantify: (1) the time that lizards stay within the retreats in the absence and presence of other lizards; (2) the individual variability in the behavior when decisions need to be taken; and (3) the individual variation in variables associated with exploratory behavior (e.g. errors after making decisions, time of exploration before finding suitable retreats) in environments where costs of thermoregulation vary. We expect to explain this variation through comparisons among treatments/enclosures and between the semi-natural and the natural populations. As a complement to laboratory experiments the manipulation of variables associated to individual behaviors in semi-natural setups will provide new insights on selection of favorable microenvironments. (AU)