Thermoregulation in Neo-Tropical Tree Frogs

Abstract

Pterorhodin, a darkening pigment that replaces melanin in some neo-tropical tree frogs, causes them to reflect light in the near infra-red. The evolutionary drive for this has been speculated to be either for enhancing the crypticity of such anurans, or to help them stay at cooler temperatures.The theoretical background is recapitulated, and the parameters associated with these processes are studied. A technique for measuring surface areas and volumes through 3D reconstruction is developed and used in the two species of the Cruziohyla genus, for which two area interpolation methods are suggested. Experimental measurements of the mass transfer coefficient are presented, and two extrapolation methods are proposed.A detailed simulation of the thermoregulatory processes in tree frogs programmed in MATLAB and made available to the public as a graphical user interface (GUI) is presented. The simulation includes all the proposed approximation values and a complete set of default values that enable the user to directly generate realistic simulations.The significance of the temperature differences between frogs with and without the infra-red reflectivity is discussed in two scenarios. The differences are concluded to be negligible in the most common scenario, but are shown to be significant when the frog is completely exposed to the solar radiation.

Date of Award	31 Dec 2015
Original language	English
Awarding Institution	The University of Manchester
Supervisor	Mark Dickinson (Supervisor) & Ahsan Nazir (Supervisor)