Backpacker Magazine – May 1998

Why Do Fireflies Glow?

Plus 24 other round-the-campfire brain stumpers every nature buff should know.

by: Phillip Manning

Tags:
• Nature
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• Wildlife
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• Mysteries
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• Feature stories
|

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Wisdom, some wise guy once said, is its own reward. Well, call me a craven materialist, but I'd rather have the Reese's Pieces. Let me explain. My hiking buddies and I like to pass time in camp trying to one-up each other with our "knowledge" of everything from backcountry diseases to astronomy. To make things interesting, we ante up whatever we find in our gorp bags:

raisins, peanuts, the usual. When the stakes get high, we pull out the Reese's Pieces. On the fourth day of a six-day trek, those little buggers are worth more than any $100 casino chips.

So when I first started ferreting out the following fun nature facts, I couldn't help but picture myself burdened with booty, cackling with peanut-butter breath at my ill-informed friends. But then my cravings gave way to something more satisfying: an appreciation for the mysteries of the wilderness we all cherish. I hope the questions and answers here do the same for you, making your next trip more enlightening, safer, and, yes, a little sweeter.

1. Can I eat bark?

"Sure you can, or at least the cambium layer just beneath the bark, but why would you?" asks Christopher Nyerges, author of In the Footsteps of Our Ancestors: Guide to Wild Foods. While the bark of trees such as alder, birch, and willow can be munched in an emergency, there are many wild foods far more palatable, Nyerges notes. The most readily available edibles include any type of grass or true cactus (not agave or century plant), any fresh seaweed, all members of the mustard family, and acorns after they are husked and boiled to remove the bitter tannic acid.

2. Why do birds fly in a "V"?

Like feathery stealth bombers, flocks fly in wedges for aerodynamic reasons, explains Karen Johnson, past president of the San Fernando Valley Audubon Society. Each bird-except for the leader-gains lift from the wing vortices of the bird in front. When the lead bird tires out, it switches places with a "wingman." Formation flying may increase the range of a flock as much as 70 percent over that of a bird flying solo. Such V-flying may also allow birds to maintain visual contact and avoid collisions, Johnson adds.

3. Why do we need mosquitoes, blackflies, and other bothersome bugs?

"First, insects are one of the main sources of high-quality food for wildlife," particularly fish and birds, says Lou Bjostad, professor of entomology at Colorado State University in Fort Collins. "Second, many biologists believe that a complex ecosystem including many species of plants and animals is a healthy ecosystem. Mosquitoes and blackflies are simply additional species."

4. Does moss really grow on the north side of trees?

Very generally, yes, because moisture-loving moss avoids the heat of southern exposure. But never rely on moss to pinpoint direction; in cool or dark forests it's common to find moss growing all the way around trees. Members of the sunflower family, such as the common, swamp, and prairie sunflowers, are somewhat more reliable. They follow Ol' Sol across the sky, facing east in the morning, south at noon and west in the afternoon.

5. How can owls fly silently and hunt in the dark?

Owls are adapted perfectly to operate after hours. According to Dr. Wes Stone of the Cooperative Wildlife Research Laboratory in Carbondale, Illinois, owls swoop silently because their wing tips are slotted and the leading edges of their flight feathers are serrated. These features disrupt air flow and eliminate noisy wind patterns. Owls hunt effectively at night because their concave face feathers channel sounds to their ears so they can track sounds. Owl eyes also have more rods than cones, enabling them to see in the faintest light.

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