Regulation of insensible evaporative water loss in birds and mammals

We have shown that birds and mammals can regulate insensible evaporative water loss, but we do not understand how or why.

This externally-funded research project investigates the recently demonstrated capacity of birds and mammals to regulate their insensible water loss (evaporative loss below thermoneutrality) rather than it being passively determined by ambient temperature and humidity, how and why do these species do it?

You will investigate control of insensible water loss for a range of species, of either parrots or dasyurid marsupials, which differ in body mass and are from different environments, to evaluate whether this capacity is an adaptation to environmental aridity or a fundamental component of the thermoregulatory control system.

To investigate a second question, how is insensible water loss regulated, you would partition evaporative water loss into its respiratory and cutaneous components, and determine how much each component is affected by ambient humidity and temperature. For whichever component is not passive to ambient humidity, you would then further investigate it to determine the mechanism for this independence e.g. skin temperature or resistance for cutaneous evaporation, or expired air temperature, oxygen extraction or ventilation rate for pulmonary ventilation.

These, or related questions would form the basis of this project, depending on your specific interests and skill set. Overall, the project would provide a much clearer understanding of the role and mechanisms determining insensible water loss, which has been historically considered to be a passive consequence of ambient temperature and humidity, for an endothermic vertebrate.