Whatever comes natural to that particular animal is the only thing that it can do. It needs to do whatever it takes to satisfy its life sustaining needs, to gratify its fleshly desires, and to protect itself from harm and attack from some other force which may be out to do it harm. The natural course of action is to find food. Of course not. Such is the nature of flesh.
Flesh lives to continue living.
Flesh seeks its own gratification by nature. If it is hungry, it seeks out food. If it is thirsty, it seeks out water. If it is cold, it seeks shelter. If there is a sexual arousal, it does whatever is necessary to satisfy that lust.