Photo: Reindeer Change Their Eyes for Summer and Winter, Study Finds



Reindeer, such as the adult female seen here on the Arctic archipelago of Svalbard, change the structure and color of their eyes in response to the seasons, a new study says.

During the 24-hour darkness of winter, reindeer eyes reflect the predominant color of blue (inset right), while in the continuous sunlight of the summer, the eyes shine yellow.

Reindeer photograph courtesy Dr. Nicholas Tyler, Univ. Tromsø; inset photograph courtesy Dr. Glen Jeffery, Univ. Coll. London


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