Thermoregulation in Neo-Tropical Tree Frogs A thesis submitted to the University of Manchester for the degree of Master of Philosophy in the Faculty of Engineering and Physical Sciences Submitted on 2015 Francisco Herrerías Azcué School of Physics and Astronomy 1 2 List of Contents List of Figures .................................................................................................................. 7 Abstract ........................................................................................................................ 11 Publications and Presentations ...................................................................................... 15 Acknowledgements ....................................................................................................... 17 1 Introduction ........................................................................................................... 19 2 Thermoregulation .................................................................................................. 21 2.1 Absorbed radiation ................................................................................................. 22 2.2 Emitted radiation .................................................................................................... 22 2.3 Conduction .............................................................................................................. 23 2.4 Convection .............................................................................................................. 23 2.5 Evaporative water loss ............................................................................................ 24 2.6 Metabolism ............................................................................................................. 24 3 Parameters ............................................................................................................ 25 3.1 Environmental ......................................................................................................... 25 3.1.1 Solar Irradiance ............................................................................................... 26 3.1.2 Surrounding Temperature .............................................................................. 27 3.1.3 Wind ................................................................................................................ 27 3.1.4 Relative Humidity ............................................................................................ 27 3.1.5 Global Position and Time ................................................................................ 28 3.2 Frog-Dependant ...................................................................................................... 29 3.2.1 Shape ............................................................................................................... 29 3 3.2.2 Position / Projection ........................................................................................ 30 3.2.3 Frog Spectra ..................................................................................................... 31 3.2.4 Convection Coefficients ................................................................................... 32 3.3 Constants ................................................................................................................. 34 4 Photogrammetry.................................................................................................... 35 4.1 Software .................................................................................................................. 35 4.2 Method .................................................................................................................... 36 4.2.1 Image Acquisition ............................................................................................ 36 4.2.2 Model Reconstruction ..................................................................................... 38 4.2.3 Mesh scaling and cleaning ............................................................................... 39 4.3 Measurements ......................................................................................................... 40 4.4 Precision .................................................................................................................. 40 4.4.1 Printed 3D Models ........................................................................................... 40 4.4.1 Known Density Objects .................................................................................... 41 5 Frog Surface Areas ................................................................................................. 43 5.1 Acquired Data .......................................................................................................... 44 5.2 Interpolation from weight ....................................................................................... 44 5.3 Interpolation from snout-vent length ..................................................................... 45 5.4 Surface area comparison ......................................................................................... 46 6 Measuring the Mass Transfer Coefficient ................................................................ 49 6.1 Theoretical Background ........................................................................................... 49 6.2 Experimental Method .............................................................................................. 50 6.3 Models and Instrumentation ................................................................................... 51 6.3.1 Agar Models ..................................................................................................... 51 6.3.2 Agar Moulds for Plaster of Paris Models ......................................................... 52 6.3.3 Plaster of Paris Models .................................................................................... 52 6.3.4 Instrumentation ............................................................................................... 53 6.4 Results and Discussion ............................................................................................. 53 6.5 Conclusion ............................................................................................................... 56 7 Frog Simulator GUI ................................................................................................. 57 7.1 Solar Irradiance Model ............................................................................................ 57 4 7.1.1 Air Mass Approach .......................................................................................... 58 7.1.2 Solar Position Calculator ................................................................................. 58 7.1.3 SMARTS Approach .......................................................................................... 59 7.2 GUI Inputs and Functionality .................................................................................. 60 7.2.1 Frog Characteristics ......................................................................................... 60 7.2.2 Ambient Characteristics .................................................................................. 63 7.2.3 Location Characteristics .................................................................................. 64 7.3 Outputs ................................................................................................................... 64 7.4 Save and Load ......................................................................................................... 65 8 Simulation Results.................................................................................................. 67 8.1 Extreme Case Scenario ............................................................................................ 67 8.2 Partially Occluded Frog ........................................................................................... 69 9 Conclusions ............................................................................................................ 73 Appendix A, Frog Simulator Code ................................................................................... 76 Appendix B, Solar Position Code .................................................................................. 114 Appendix C, Solar Spectrum Code ................................................................................ 116 References .................................................................................................................. 137 Final word count: 33,458 5 6 List of Figures Figure 1.1 Photographs of Cruziohyla craspedopus (Top) and Cruziohyla calcarifer (Bottom), on which the surface area studies were focused. ...................................................................... 20 Figure 2.1 Diagram of the power exchange processes considered in the thermoregulation model. Absorption of solar radiation considers scattered, reflected direct and indirect sunlight, and it can only have a positive sign (going into the frog). Conduction and grey body radiation and convection can take either sign, and although evaporative water loss could too, it usually has a negative sign. ..................................................................................................................... 22 Figure 3.1 Samples of the solar direct (red) and diffuse (blue) spectra at different zenith angles.