This project aspires to further our understanding of ventilatory control in mammals, with special regard to changing body temperature and extreme conditions of gas exchange. Small bats will primarily be used because they are uniquely suited for revealing the processes of ventilatory control under these conditions. The extreme energetic demands of flight provide a system in which to probe the upper limits of mammalian respiratory function. In addition, the ability of small bats to reduce their body temperature and metabolism through torpor permits the exploration of ventilatory control when operating in its most reduced extreme. Exploring ventilatory control processes in whole animals is often thwarted by the experimental process itself, because ventilatory control is subject to conscious override. However, a further advantage of torpor is that it provides a state in which ventilatory processes may be investigated free from conscious interference, thus assuring dependable data. Experiments will be performed using a variety of innovative techniques specially designed for bats. This study will help elucidate physiological control mechanisms regulating 1) unusually low and high metabolic states, 2) different patterns of ventilation, and 3) the adaptation to environmental changes. This investigation of undisturbed integrated function will also provide important corroboration of investigations that involve non-intact ventilatory components and more invasive techniques.
