Reindeer Change Their Eyes for Summer and Winter

Scientists say the animals change their eye color and structure with the seasons in Arctic regions where permanent summer sunlight is replaced by 24-hour darkness in winter.

The visual alterations appear to be an adaptation to deal with polar light extremes, according to the researchers from Norway and the U.K., who add that the phenomenon has never before been recorded in mammals.

The researchers studied reindeer from the Lapland region of northern Scandinavia and found that eyes removed from animals culled in winter appeared deep blue when light was shined into them. But the eyes of summer reindeer were yellow in color.

Link & Image: National Geographic
Tags: Eyes | Reindeer | Animal | Nature