The Woolly Bear Caterpillar
Look down on a warm, sunny fall day and you might see a fuzzy, black caterpillar with a reddish-brown band around its middle. The woolly bear caterpillar, or woolly worm, is a beloved part of our fall culture as a predictor of winter weather. Legend has it if the red band around its middle is wide, the winter will be mild. If the red band is narrow, you’d better have the snow shovels ready. And if you see them inching their way south, that means they’re running from colder weather.
Jody Green is an extension educator at the University of Nebraska. She says the myth picked up steam in 1948 by an insect curator at the American Museum of Natural History in New York City.
"He collected woolly bear caterpillars for a number of years and measured their little midsection, that reddish area, and then he tracked the weather patterns," says Green. "Evidently, it’s been debunked so it no longer stands because there are scientific reasons why some of those bands are narrower and wider."
She says the width of the red band probably has more to do with past weather than future. Good weather conditions produce growing caterpillars.
"The caterpillars have 13 segments, they can count the number of segments that are changing color. So, what happens is as they age, they actually get a larger band. And so, older caterpillars are going to have a larger red-brown band," says Green.
Even though there’s no scientific evidence the caterpillars know something we don’t, it’s still fun to think about.