Q. There are a lot of deer-like animals from all parts of the world. If you examined them all, you will discover an interesting trend. Those that live in tropical climates like the savannas of Africa are usually much smaller than the ones that live in arctic regions like Lapland. Note that heat generation is metabolic - it's a result of the chemistry that goes on inside the body - and that heat loss is a surface function. Describe this interesting size gradation.