Q: Does the early bird really get the worm?
Jayne Mueller, Long Island, New York
A: Yes, but the lazy lion gets the zebra. All animals are equipped with a biological clock that regulates basic bodily functions such as when they sleep, when they're most alert, etc. In humans (and most mammals), the clock is housed in the hypothalamus, a part of the brain just above the back of the throat that uses information gathered from the eyes to synchronize our body with the 24-hour day and releases important neurotransmitters like histamine, which signals us awake. Worms surface during the night and burrow back underground in the morning. Thus; a bird's clock triggers it to wake at dawn, before the slithery annelids retreat to safety. Lions and other cats, however, don't seem to be tightly controlled by a body clock. They'll steal the kill from a pack of dingoes at night or stalk zebras in broad daylight. Their slothful reputation can be attributed to the African lions of the eastern Serengeti, which lie in wait along migratory routes because they know their dinner will likely walk right past them en route to water. "They're hardly lazy," says Barry Wakeman, retired director of education at the Cincinnati Zoo. "But smart? Yes."
Q: I've heard that it's possible to survive in the wild by eating snow and drinking your own urine. True?
Mark Stefanelli, Seaside, Oregon
A: Since snow is nothing more than standard-issue H20 packaged in crystal form, you can gorge on all the white stuff in your neighborhood, so long as you use common sense (i.e. don't eat snow that's the color of snowblower exhaust). But in an acute survival situation, there are more important guidelines to follow. According to Peter Hackett, the world's foremost high-altitude physician, the first rule is to determine how you feel. Hackett advises against eating snow if you're shivering or if you were previously shivering and now feel lethargic or delirious, all warning signs of hypothermia. Eating snow will only lower your already plummeting core temperature. (Let it fall to 60 degrees Fahrenheit and you're never going to warm up.) As for alternative beverages like, well, your own pee...don't even think about it. While urine is 95 percent water, the other 5 percent consists of diuretic urea, creatine, and several other waste products. Each sour slurp restokes your body with the same salts and acids it was trying to expel; your kidneys produce more urine and you grow even thirstier. So do yourself a favor and resist the allure of a tinkle cocktaileven if the producer of Survivor III tells you it'll make great TV.
Q: Do lakes really die? I heard several years back that Lake Titicaca had died. If so, how and why?
Oleta Longmire, Big Cabin, Oklahoma
A: The term "dead lake" is misleading. Often it's used to describe a lake that has suffered a major fish kill because of acid rain. But while those particular fish are gone forever, a dead lake can eventually be brought back to life by adding massive amounts of lime to neutralize the acid. Ironically, in other instances, a dead lake can actually have too much life. When agricultural fertilizers drain into a lake, algae fed by the nitrogen and phosphorous bloom in such huge quantities that they smother the fish. Thankfully, three-million-year-old Titicaca is still alive, despite having had a tough go of it during the last several decades. In the early 1940s, at Peru's request, the U.S. Fish and Wildlife Service stocked its 3,200 square miles with common North American rainbow trout, believing that would help feed locals living along the shore. But the plan backfired when the hungry trout nearly eradicated two native fish species, the boga and the humanto. Tourist accommodations along the lake-shore, many of which allow raw sewage and chemicals to drain directly into the water, haven't helped either. But, says Ben Orlove, author of Lines in the Water: Nature and Culture at Lake Titicaca, "Compared to other ancient lakes, Titicaca is in pretty good shape."
Q: When I fly my paraglider I sometimes see a bright light where my shadow should be. Am I glowing?
Eric Reed, San Francisco, California
A: Uh, no, but you are having a lesson in the bizarre, little-known science of atmospheric optics. This enlightening phenomenon is called a dry heiligenschein, or "holy light," and you don't have to leave the ground to observe one. On a sunny day, stand on some grass and look at the shadow of your head. Just outside the shadow you'll notice a halo; it's bright there because you're looking directly along the lines of the sun's rays and can't see the shadows cast by the leaves of grass. Now look several inches outside the halo. There, the rays are striking the grass at an angle with respect to your line of sight, so you can see the grass cast little shadows off to the side; the effect is darker-looking grass. Put the two phenomena togetherthe halo and the shadow ringand the contrast causes the halo to appear even brighter. As a paraglider, you'll witness the same effect when the sun is high and you're soaring over a grassland, thick forest, wheat field, or other similarly shaggy surfacebut as you gain altitude, your shadow will shrink until it disappears, the bright spot will take its place, and a heavenly specter will follow you below.