Memo to Rihanna: Falcons DO Close Their Eyes When They Sleep

Pop phenom Rihanna took to Twitter on June 23 to share her new ink: a tattoo of an Egyptian Falcon perched on her right ankle.

“Falcon: a light that shines in the darkness! Never close their eyes during sleep,” Rihanna tweeted with an image of the design.

Which begs the question: Do falcons really sleep with their eyes open?

Not according to John Parks, a professor of animal sciences at Cornell University and Director of the Cornell Raptor program.

“When they sleep, not only do they close their eyes, but they tuck their head under their wings, over their backs, so it’s somewhat concealed,” says Parks. They blink their eyes, too, when they’re awake. And the birds have a “nictitating membrane,” often called a third eyelid, that they can lower to protect their eyes and keep them moist when flying.

But Rihanna can take solace in the fact that falcons have singularly beautiful eyes, larger and darker than those of most other raptors. Falcon eyes have other noteworthy characteristics. They’re set comparatively farther forward in their heads, enabling them to put prey in their sights more easily. And they can see things that humans can’t. A falcon can view the full spectrum of colors much more clearly and from greater distances than we can. They can also perceive ultraviolet light. The American kestrel, for example, can see the ultraviolet wavelengths in the urine of mice and other small prey, allowing them to track a creature more effectively.

-Kastalia Medrano