Prince was on the bleeding edge of so many things: music, fashion, sexuality. So it’s not surprising that his hit “When Doves Cry” raises more questions than it answers. How did Prince’s home life affect him as a lover, and a song writer? Is he ashamed of being like his father, or his mother? A more curious question, however, doesn’t come from human nature, but ornithology—can doves actually cry?

Grief is not the only reason humans cry. There are “happy” tears, tears of relief, and tears that function only as the windshield wiper fluid of the eye. Birds, and doves specifically, can and do produce tears of the latter version. An animal can produce tears if its eyes are outfitted with lacrimal glands. Doves have them. But animals with a so-called “third eyelid,” a nictitating membrane, have a special type: a harderian gland.

“These glands  produce tears all the time, because their function is to keep the eyes lubricated and free of debris,” says science writer Jason Goldman. Doves then, are always crying. “Whether doves can feel sad is, of course, a separate question, as is whether sad doves produce an excess of tears the way humans do.”

“As for a sound, I suspect that grieving doves – if they do grieve – probably produce tears silently.”

It’s poetic, in a way. What it sounds like when doves cry is silence. Maybe that’s how a dove’s father sounded. Or maybe it’s just like its mother. Or more likely, birds can’t cry aloud because, as Goldman points out, “if you’re a bird, you need to be judicious in the use of your calls, or else you might attract the attention of a hungry predator.”

But as Prince knew, sometimes attracting attention is a good thing.

Image: Warner Bros.

Kyle Hill is the Science Editor of Nerdist. Find him on Twitter @sci_phile.