How Can a Butterfly, Weighing No More Than a Feather, Fly Into the Wind?


This question, from our brilliant reader Greg, is actually rather poetic, isn't it? It's so wonderful that I want to write it out again:

How can a butterfly, weighing no more than a feather, fly into the wind?

Ahh, that felt good. Okay, to the question. How is this possible? How can a butterfly, so slight, with its wings made seemingly of lace, take to lapis summer skies in the face of buffeting winds?

O Hark! Butterfly, fluttering
Between the Earth and heaven
Against the cool, slippery hand
Of wind's wanton wail

Ack, sorry again. Got carried away. Right. Butterflies. Wind. How does it happen? We contacted Professor Robert Dudley, head of the Animal Flight Laboratory at U.C. Berkeley to find out. He says that, no matter the animal, if wind speed exceeds maximum flight speed, then it can't fly. Different species of butterflies fly at different speeds, and the range is about 1.5 to 10 meters per second (~3 to 23 miles per hour). If the windspeed is any higher than that, then the butterfly isn't slipping the surly bounds of Earth to cut through it.

Professor Dudley also says that many small butterflies avoid high winds as they would merely drift. A butterfly's wing is more suceptible to ambient winds, so, while capable of flying into the wind, they aren't exactly engineered for it.

That ain't poetry, it's science.