Tree-hugging koalas demonstrate a novel thermoregulatory mechanism for arboreal mammals

Abstract

How climate impacts organisms depends not only on their physiology, but also whether they can buffer themselves against climate variability via their behaviour. One of theway species can withstand hot temperatures is byseeking out cool microclimates, but only if their habitat provides such refugia. Here,we describe a novel thermoregulatory strategy in an arboreal mammal, the koala Phascolarctos cinereus. During hot weather, koalas enhanced conductive heat loss by seeking out and resting against tree trunks that were substantially cooler than ambient air temperature. Using a biophysical model of heat exchange, we show that this behaviour greatly reduces the amount of heat that must be lost vi..