12.3 Energy Balance

Assuming that an animal’s body temperature is constant (steady state), energy input to the animals must equal energy out. We can write the animal’s energy balance as follows: $$\begin{equation} M + R_+ = R_- + C + H + E \tag{12.1} \end{equation}$$ where $M$ is the metabolic rate, $R_+$ is the amount of radiation absorbed by the animal surface, $R_-$ is the thermal radiation emitted from the animal surface, $C$ is the heat conducted from the animal to any surface it is in contact with, $H$ is the heat loss from the animal to the environment via convection, and E is evaporative heat loss.