Owl-style survival gear
/SCIENCE SKETCH: a quick look at some new science
Tawny owl feather anatomy
Tawny owls come in two colors, gray or brown. Research in Finland has shown that the brown morphs fare poorly during harsh winters. Do the gray morphs have feathers with better insulation?
Looks like they do, according to a recent study. The fluffy inner part of the feather was denser for gray morph owls than for brown morph owls. Hurrah!
How is this extra insulation tied to other gray morph attributes (like the gray color itself, for a start) that could be somehow involved in surviving the cold and snow? That's not all clear.
The hardy gray Morph (L) and the less-insulated brown morph (R)
In any case, having two morphs sounds like a handy trick for this widespread owl, which is found across Eurasia. Gray morphs might do better in the cold, but brown morphs seem to thrive in warm and humid conditions.
This may give the species some flexibility in coping with the climate.
See the study in Journal of Avian Biology.