...and other seemingly far-fetched but true superstitions about animals, insects and plants
What some people won't do for a little luck. Take, for instance, the Italian violinists of the seventeenth century who kept toads in their violin cases to improve their performances. Just before a concert, the musicians pulled out their toads and stroked them, believing that the amphibians would keep their hands from perspiring.
Silly as toad-rubbing may sound, modern science has shown that the Baroque violinists may have been onto something. According to William Dullman, a herpetologist at the University of Kansas, most species of toad secrete an alkaloid substance that tends to dry out human skin. "That's why little cuts can be painful if you're in the habit of playing with toads," he says. "It's like dabbing wounds with alcohol."
For centuries, people have had some pretty strange superstitions about the natural world. Scientists have debunked many of these as just so much coincidence sloppily observed. But in some cases these superstitions have come from keen observation of nature and have more than a grain of truth in them. Following is a look at some of the other odd-sounding, but true, superstitions about animals, insects and plants.
People have been trying to rid themselves of fleas for centuries, and yet, for almost as long, Europeans have believed that it is a bad omen for fleas to depart too suddenly.
Fleas are sensitive to increases in the body temperature of their host. So when people or animals run dangerously high fevers, fleas often evacuate.
Smithsonian Institution entomologist Robert Traub says such a fever might be brought on by illness or trauma. "Trappers, for instance, have often witnessed dozens of fleas jumping off an animal facing death in a trap," says Traub. "This is partly because the animal's hair is probably standing on end, so the fleas are exposed. And it's agitated so its temperature would be higher."
Sixteenth-century voyagers witnessed a similar flea exodus when they traveled to the New World. They wrote about arriving at a longitudinal point in the tropics—the so-called "louse line"—where fleas and lice abandoned even healthy humans. Although a specific line is myth, cultural entomologist Charles Hogue of the Natural History Museum of Los Angeles believes part of the story. "Voyagers in the tropics often experience a rise in body temperature of as much as 4 degrees F." That's enough, he says, to kill some species of stowaway fleas.
Since a vacation in the tropics hasn't been an option for most people plagued by fleas, folklore is full of wacky, but unfortunately ineffective, flea repellents. A British folk remedy says to sprinkle the house with dirt scooped from beneath your right foot when you hear the first cuckoo call of the year. Of course, the United States doesn't have European cuckoos, so Americans may substitute another old remedy, burning a dirty dish cloth when the first thunder cracks in March.
Folklore from Florida swamp country is full of tales of the ferocious crocodile, a beast supposedly so malevolent that it seeks vengeance on people it knew as enemies in another life.
Alan Woodward of the state of Florida's Fish and Wildlife Research Unit says he doesn't know if crocodiles are reincarnated, but does think they have a knack for shadow-grabbing.
"As a rule of thumb, if you're close enough for your shadow to touch the water's edge," explains Woodward, "then you're close enough for a crocodile to grab you."
The reptiles are extremely quick and have good eyesight. They usually spot their prey along the bank and wait for it to get close before striking. "Crocodiles also start feeding at dusk. So the longer the shadow, the closer to nighttime, and the more aggressive the feeding behavior," says Woodward.
Even so, he feels the danger from American crocodiles is overrated, because they prefer to eat small mammals, not humans. The creatures' bad reputation may have come from the Nile crocodile of Africa which does sometimes devour people.
A tall black bird with a bare wrinkled head hovers over its victim waiting for it to die, then drops out of the sky to feast on the carcass. Such an animal is bound to encite superstition. In the Deep South, old tales warn that the mere shadow of a buzzard can kill. And native Americans believe that buzzard feathers are so powerful they can drive an enemy crazy if the feathers are thrown into a running stream at midnight.
It seems, though, that southern slaves had a legitimate observation about the buzzard. They called it a thief-finder because they believed the birds could spot a guilty conscience a mile away—and they can if the stolen goods are pieces of meat.
Although the buzzard doesn't have the supernatural "sixth sense" that slaves thought it did, some species do have a highly developed sense of smell, unusual in birds. Thus a buzzard could detect anyone smuggling meat out of the plantation's main supply. Sometimes before the hidden meat had begun to smell to human noses, buzzards appeared, circling the culprit's quarters.
The "buzzards" were probably turkey vultures or black vultures, both common in the region, says raptor expert John Coleman of the University of Wisconsin. "Turkey vultures can smell dead meat at least a quarter of a mile away," he says.. "It's useful for finding smaller carcasses like mice."
Black vultures can't smell quite as well, he says, so they look for circling turkey vultures to find a meal. "Of the two, black vultures are more comfortable around humans, so they'd land right on the roof."
Folklorists think this belief is based on goldfish, a variety of carp. Ever since the Chinese introduced the first goldfish to an ornamental pond more than 800 years ago, people have been fascinated by the fish's hardiness and longevity. And because goldfish don't get wrinkles or gray hair, they might appear to stay young forever.
But the truth is more than scale deep. Paul Loisell, curator of freshwater fish at the New York Aquarium, points out that some species of carp stay youthful in the sense that they never stop growing. "Their tissues continually regenerate. So they simply don't wear out the same as humans," he says. "Their life span is not fixed like ours."
Carp don't live forever, though. Environmental factors eventually kill them, says Loisell.
Fish breeders tell stories of 300-year-old Japanese Koi goldfish passed down as heirlooms, but scientists are skeptical. Judging a fish's age is not easy. Counting growth lines on scales does not give a reliable age because the fish lay down extra lines when confined in a bowl or pond. Most fish specialists agree, however, that goldfish can live more than 50 years, making them the longest living fish next to lake sturgeon.
Science is finding a drop of truth in the advice to eat carp to stay young. Many fish species contain high levels of Omega-3 fatty acids, which reduce the risk of heart disease in humans, according to the National Institutes of Health. Populations with diets that consist largely of fish do, in fact, have longer life expectancies.
Wherever there are mosquitoes, there are people thinking up ways to keep them from biting. Folklorists have recorded only one remedy that might work: holding your breath.
Mosquitoes are attracted not only by sweat and warm, moist air, but by exhaled carbon dioxide, according to entomologist Dennis LaPoint at the University of Massachusetts. "Your breath is actually an activator of host-seeking behavior, stimulating them to bite," he explains, adding that scientists use carbon dioxide to attract mosquitoes in experiments.
If it's going to rain, the scarlet pimpernel closes its petals before 2 p.m.
European legend has it that holding the starlike flower of the scarlet pimpernel gives the power of second sight. Since the flowers can be used to predict rain and to tell time, it's no wonder that people considered them magic. "Plants have an internal time clock that helps them gear up physiologically so that they don't waste time or energy," says biologist Kathleen Horwath of the State University of New York. She studies how the flowers' clocks interact with bees' biological clocks.
Bees have an internal mechanism that gives them "time memory." When they find a cache of flowers like scarlet pimpernels that open up at a certain time, the insects report to the rest of the hive not only the location of the cache, but when the flowers open. Both the bees' and the flowers' clocks are synchronized with sun movements.
On a sunny day, the scarlet pimpernel opens at 7 A.M. and closes at 2 P.M. A sudden decrease in sunlight, like the darkness before rain, cues the flowers to override their biological clocks and close their petals early. Flowers protect their pollen this way.
Horwath suspects that plants coevolved this mechanism with pollinating insects. "Bees," she explains, "don't venture out in the rain, so it's of no benefit for a plant to have its petals open."
A spider is the last thing many parents want dangling over their infant's cradle. Chippewa Indians of the Great Lakes region, however, believe spider webs over a cradle bring good luck by catching the "harm in the air." The Indians collected webs on hoops and hung them whenever one wasn't spun.
Folklorists say that "harm" means evil spirits. But according to researcher Joe Raver of the University of Cincinnati, the webs may have acted as primitive mosquito netting.
"A net made of spider web, probably from an orb weaver, would be extremely strong and moisture resistant," says Raver. It could hold up for days indoors, trapping potentially harmful insects. "Mosquitoes and black flies are especially bad in the Great Lakes region," he adds. Mosquitoes carry encephalitis, and black fly saliva can cause severe allergic reactions, especially in children.
Chippewas were not the only ones to use spiders to ward off illness. Medieval Europeans tried a few methods, but most were too bizarre to be effective. One such treatment involved wearing a spider in a silk bag on a necklace to prevent diseases from arthritis to consumption.
Badgers have been associated with medicine in many cultures. In Italy, for example, a traditional baptismal gift to ward off disease and evil spirits was a small tuft of badger hair enclosed in a tiny gold case. Even today some Belgian farmers tie badger hair in red flannel to keep their cattle from getting sick. Folklorists aren't sure how these associations came about, but for Indian tribes of the southwestern United States, connections between badgers and medicine seem valid.
In much tribal lore, the badger was a medicine man who knew which roots were good for treating certain ailments. This idea stems from American badgers' style of kicking up roots as they dig furiously for mice and other small prey.
"Badger holes are often found at the base of plants, like sage, because the plants serve as perch sites and provide protection for the prey from aerial predators," says University of Montana biologist Steve Minta. He speculates that Indians often used badger holes as easy places to collect roots.
According to James Duke, an ethnobotanist with the U.S. Department of Agriculture, many of the roots Indians collected had real medicinal value. For instance, says Duke, "tea made from sage root is known to alleviate the symptoms of colds and asthma."
Blazing star, another plant found in badger country, is a natural diuretic that relieves minor bladder and kidney ailments. Perhaps the most widely used root was coneflower, says Duke. Chewed, it can ease the pain of toothaches, canker sores and sore throat. Ground into a salve, it has antibacterial properties similar to cortisone.
A cricket singing on the hearth is considered a token of luck in almost every part of the world. In Oriental cultures the cricket's chirp is enjoyed for its beauty and is considered the sound of a happy home, but Americans have discovered a practical use for the bug.
According to entomologist Timothy McCabe of the University of New York, crickets make good thermometers because the hotter the weather, the faster they chirp. "A cricket's metabolism speeds up as it gets hotter," explains McCabe. The body is "not as stiff, so it can react faster than it can at lower temperatures."
For most cricket species, only the male chirps, usually to attract a mate or repel other males. The male snowy tree cricket, common throughout the United States, tracks temperature so consistently that in 1897 a physicist developed a measurement formula, accurate to within 1 degree F: Count the number of chirps in 15 seconds and add 39.
Throughout history, cats have been associated with all kinds of strange superstitions. For centuries, many sailors claimed to raise winds at sea by placing the ship's cat under a pot. Germans have long believed that cats can help see ghosts—just look between a cat's ears. In the United States, though, New Englanders have come up with a cat trick that really works—using the creature as a clock. As Wisconsin optometrist Les Thornburg explains, the construction of the cat's eye makes it an adequate timepiece.
Cats have a built in reflector in the back of their eyes called a tapetum. This layer makes their eyes appear to glow in the dark. The tapetum allows cats to see with only one-sixth of the light that humans need, but it also makes cats' eyes very sensitive to bright light.
To compensate, cats have elliptically shaped pupils. "A cat's pupil has a wider range of movement than a human's," says Thornburg. "It can open completely round at night and close to just a slit during the day. So I guess you really can tell time by the shape of the cat's eye."
Watching the sun's position in the sky might be more accurate, but not nearly so romantic. Egyptians were so captivated by the cat's powerful, glowing eyes that they worshipped Felis sylvestris, ancestor of our domestic cat. They sometimes saw wild cats feasting on the entrails and liver of their prey before turning to the rest of the meat, so cat worshippers ate liver hoping they too would see at night. As it turns out, liver is rich in vitamin A, a cure for night blindness.
Donna Johnson, who have five cats to help her tell time, is on the staff of National Wildlife.
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