Higher elevation birds sport thicker down

A new study examines feathers across 249 species of Himalayan songbirds, finding that birds at higher elevations have more of fluffy down than lower elevation birds. Finding such a clear pattern across many species underscores how important feathers are to birds’ ability to adapt to their environments. Furthermore, finding that birds from colder environments tend to have more down may one day help predict which birds are vulnerable to climate change simply by studying feathers.