You can see the principle at work in this picture. In the left-hand picture the ears would be invisible.

The closer you get the more the ears become hidden. So, I don't know whether Fetter's ears have had some "help" along the way but I do know that standing closer can make you nose bigger and your ears smaller.

Think of photographing two identical objects with one 6' away and one 12' away. The far object will look half the size of the near object. So if you ears are twice as far away as your nose that affect will apply.

It caught out the mappers who used photographs as well. The tops of mountains were much closer than the bottom of the valleys so their size was exaggerated. That has to be compensated for.