BACKS TO THE WIND
Sounds and smells are carried by the wind. So, when outside and on the lookout, it makes sense to sit or stand with your back to the wind, downwind. Upwind, in front you can use your eyes. Then listen and smell with each change of wind.
I don't know if this checks out in animal behaviour, but imagine it must, animals who were only aware of what was upwind, i.e. were looking in the direction of the wind... would all have gotten eaten, by the predators who were downwind of them.
Please continue with Ancient and Modern Smells and Animal Rights