For many years, scientists have known of how the red or yellow colour of feathers is achieved. These colours come from pigments in food the birds eat, meaning that they are diet based. One of the challenges in avian colour has been to figure out how the #blue colour is achieved. Interestingly, it came to…
via Top 25 Wild Bird Photographs of the Week: Blue — National Geographic Society Newsroom
theroostonline.blog 