Twice a Year, Reindeer Eyes Pull Off a Wonderful Magic Trick The Arctic can stay perpetually dark for months. Reindeer cope by changing part of their eyes from gold to blue. Of all the eyeballs in Glen Jeffery’s office, only a very small minority are his. “Oh, I’ve got an office full of eyes,” Jeffery, a neuroscientist at University College London, told me. Over Skype, he fi