Comparative Microscopic Anatomy And Tensile Strength Of Plumage From Various Color Phases In The Eastern Screech Owl (MEGASCOPS ASIO)

The Eastern Screech Owl (Megascops asio) is a polymorphic species with rufous and gray tones that exhibits clinal variation. The rufous morph is virtually nonexistent in the northern and westernmost parts of its range. The rufous morph predominates in humid deciduous areas in the center of the eastern screech owl range. While color polymolphism is exhibited widely in birds there is no apparent explanation for the maintenance of clinal variation. Studies have noted differences in oxygen consumption across eastern screech owl color morphs. Differences in feather morphology could lead to difference in thermal insulation and physical resistance.