Can Caribou See Ultraviolet Light?

Reindeer — the domestic cousins of the wild caribou that roam Alaska, Canada and Russia by the hundreds of thousands — can perceive ultraviolet light invisible to humans, perhaps lending the species a stark evolutionary edge in its struggle to find food and avoid predators during the long, dark night of Arctic winter.

What species can see ultraviolet light?

What they found suggests that most mammals can, in fact, see UV light—including dogs, cats, ferrets, and reindeer. Unlike humans, these mammals have lenses that allow UV light though.

How do caribou see?

As it turned out, the study revealed that reindeer were able to see light wavelengths around 350-320 nanometers (nm), well outside of the so-called visible spectrum. And the ability to see the shorter wavelengths, researchers realized, gives caribou an important advantage in their harsh environment.