A very rough sketch I did last summer. Experimenting with different types of human folk and whether or not I am going to base their appearance on what part of the world they are from, showing some form of rapid evolution.
Cliff folk for example would evolve around the harsh conditions of the sea, living on high cliff edges and gal force winds. Birds thrive in these conditions for many reasons, living high up safe from predators and with wings to guide them to the sea and back for food. So for these reasons the Cliff folk have taken on a very bird like appearance.