Every fall ruffed grouse grow skin-like fringes called pectinations on either side of each toe. They serve as snowshoes, helping grouse stay on top of the snow when walking, and also help them cling to icy branches while eating the buds of poplars and other trees in the winter. In the spring grouse shed these adaptive fringes. The bird whose foot is in this photograph met its untimely death about a week ago (they frequently fly into windows, as this one did), and I was curious to see the stage of development of the pectinations at this time of year. They appear to be about half to two-thirds the size they will attain when fully developed.