BIO120H1 Lecture Notes - Lecture 15: Blubber, Sun Bear, Woolly Mammoth

• School: UTSG
• Department: Biology
• Course: BIO120H1
• Professor: Spencer C H Barrett

Document Summary

Radiation heat transfer by electromagnetic radiation. Conduction transfer by direct contact with substrate (ex: feet loose heat to ground) Convection heat transfer mediated by moving fluid (usually air or water) Evaporation efficient cooling from wet surfaces. Redistribution circulatory system redistributes heat among body parts, especially core to appendages. Size matters to heat balance (and other balances of gains and losses) Surface area what is radiating heat; determines equilibrium rate. Volume provides the inertia; more volume=more heat. Biggest land mammal today however, in the fossil record, there is a woolly mammoth. Works from sa to volume ratio -> want to minimize this when living in colder climates which is the largest land mammal -> lived in colder temperatures. Sphere minimizes sa to volume ratio; flat piece of paper maximizes sa to volume ratio. Sometimes particular shapes are needed for function resulting in trade-offs and adaptive compromises.