Do Elephants Jump? (25 page)

The operative word in this mystery is
seem
. For all of our meteorological experts agree with Harold Brooks, the head of the Mesoscale Applications Group of the National Severe Storms Laboratory in Norman, Oklahoma, who states:

In other words, tornadoes are non-discriminatory offenders, and are subject to the laws of probability. The land covered by major population centers is tiny compared to the total expanse of North America, but a big city is theoretically just as likely to get hit as all the local trailer parks if they covered as much of an expanse as the downtown area.

There are portions of the United States where tornadoes are much more likely to hit, however. Tornadoes have been tracked in all fifty U.S. states, but the so-called tornado alleys are the Midwestern area from Texas all the way north to the Canadian border, in the southeastern United States, and in the Ohio Valley and southern Great Lakes region, extending as far east as western Pennsylvania. But within that general area, trailer parks, skyscrapers, the Mississippi River, or the Dallas Cowboy cheerleaders can’t stop tornadoes.

One other reason why the perception may have spread that tornadoes don’t hit big cities is that many of the densest population centers, such as the Washington, D.C.–to–Boston and the San Diego–to–San Francisco corridors, are outside of “tornado alley.” Even so, tornadoes
do
sock big cities. Chuck Doswell, senior research scientist at the Cooperative Institute for Mesoscale Meteorological Studies, wrote us:

Dr. T. Theodore Fujita, a tornado scientist who developed the scale commonly used to rank the severity of tornadoes, considered the role of skyscrapers and population density in thwarting the development of small tornadoes. The University of Chicago professor, who died in 1998, noted that since 1921, “practically no tornadoes occurred or moved across the central portion of Chicago.” Fujita theorized that perhaps the city’s higher temperature than surrounding areas (a phenomenon we discussed in our first book,
Imponderables
) and its man-made structures might be “acting against any tornado activity over the city.” Other major population centers that have been studied for tornado patterns, London and Tokyo, also seem to enjoy a relative dearth of small-tornado activity. But no expert seems to seriously think that even the highest skyscraper in the largest metropolis would scuttle an intense tornado from unleashing its fury.

Are there really insects so vile, so vicious, that they attack only innocent children? Maybe there are, but head lice are equal-opportunity pests. Anyone, young or old, white or black, male or female, is susceptible.

But that doesn’t mean that head lice don’t have preferences. According to the research of entomologists at Clemson University, every year 6 to 10 million people in the United States have head lice, with approximately three-quarters of them schoolchildren younger than twelve years old. If you’re a head louse, your target demographic is three to eleven. This is true all over the world: Recent studies in France, Denmark, Atlanta, Israel, and Korea all found that at least 3 percent of elementary school children were infected by lice or nits, some at twice that rate.

Lice aren’t demanding creatures. They just want to suck a little of your blood. All three varieties of lice (head, body, and “public”) feed on mammals, but head lice are found only on humans. A louse has six legs and is incapable of flying or jumping, so they cling to human hair and bite through the scalp, creating a tiny opening to suck the blood. Without a blood host, head lice are likely to survive for only a day or two.

As if having a louse on your head wasn’t lousy enough, the females have the nasty habit of laying eggs, or nits, in our hair, usually near the scalp, at a rate of about six to ten per day. Lice manufacture an insoluble cement that makes the eggs cling to our hair, so standard shampooing will not get rid of the nits. The egg hatches in about eight to ten days, and becomes an adult in another week to ten days. The adults only live for a month or so, but considering the rate at which they manufacture nits, that is of little solace.

We hope we will not be accused of nitpicking when we point out that lice eggs are often confused with dandruff or dried-up hairspray, as they are a similar color and size. But while dandruff and caked hairspray will brush out easily, nits usually can’t be extricated even if you go over it with a fine-toothed comb, although the closer the teeth in a comb are, the more likely you are to rid yourself of lice and nits.

While body lice tend to invade folks with poor hygiene, and “public” lice (the euphemism for “pubic lice” or “crabs”) are often sexually transmitted, there is no reason for social stigma about having head lice. Head lice are usually spread from person to person by direct contact, but they can also move to an object that has been used by an infected person, and transfer to another.

Head lice are perfectly content to reside on graybeards if given the chance, but kids provide more opportunities. Santa Monica, California, dermatologist Joseph W. Landau has seen several epidemics of lice in schools. Kids are less likely than adults to know whether they’ve been infested, and one kid can spread it to scores of others before treatment is provided.

More important, kids in school are constantly playing with one another, roughhousing, and touching. Girls tend to have more head lice than boys, probably because close contact is more socially acceptable, and they tend to share hats, combs, and hair accessories. Slumber parties can involve sharing more than s’mores.

Other perfectly innocent behaviors can cause louse problems. Kids are just the right height to spread lice in chairs, whether in a movie theater, a restaurant, an airplane, or most commonly, a school bus — their head hits the seat back, and the fleeing louse parks itself in the upholstery. The next person who sits in the chair is likely to find a new blood-sucking pal. Lying on a rug after an infected person has occupied the space makes you an equally compelling target. Parents of infected kids are just as susceptible to attracting head lice, and sometimes they succumb, but the parents are likely to take preventative measures, such as medicated shampoos, once they know their offspring has lice. If they don’t know about their progeny’s condition, and happen to use a towel with which their infected child dried his or her hair, they will be lousy with lice.

Although head lice are annoying, they are not particularly dangerous. In fact, the harshness of some of the remedies can be worse than the itching and occasional resultant rashes and infections that arise from scratching. Probably because of the social stigma of other kinds of lice, schools sometimes overreact when there is an infestation, and send parents a warning when even one child is known to be infected. Richard J. Pollack, of the Harvard School of Public Health, rails against the prevalent “no-nits” policy of many schools in which infected children are automatically sent home until nit-free. Pollack’s experience with samples sent in for diagnosis is that even among those that contained real louse eggs, “many were comprised solely of hatched or dead eggs; thus no treatment would be warranted.” In a few cases, courts have ordered child custody be taken away from parents who failed to eliminate infestations.

Back in the day when a certain master of Imponderability was in grade school, about the worst thing that your enemy could say about you was that you had “cooties.” Perhaps we are no more enlightened today.

Next time you go swimming in a pool, please note that large quantities of water are quite capable of being held in rectangular receptacles, square ones, and even trapezoidal ones. But if you try
constructing
a trapezoidal pool, you’ll wish you were building a round one. Most wells are round because fashioning a round well is easier than building other shapes. And in this case, easier means cheaper. Kevin McCray, of the National Ground Water Association, wrote to
Imponderables
:

Round wells have an illustrious history, dating back to the Chinese about 4,000 years ago, and to some extent, modern construction methods are just an automated version of what workers did by hand millennia ago, as McCray explains:

The occasional square well can be found, as McCray implies, mostly in undeveloped nations. Wells have a nasty habit of caving in. The best defense against a cave-in is lining the inside of the well. Shifting of the earth, severe weather, or earthquakes can cause caveins, but at no time is the danger greater than during the construction of the well itself. The only obvious reason to construct a square or rectangular well, unless there are space or aesthetic considerations, is because of a lack of lining materials that can be curved to fit a round well. In poor countries, flat wood boards are sometimes used for lining, despite wood’s obvious inappropriateness for holding water, and anyone poor enough to use untreated wood to line a well is unlikely to have the tools necessary to form the lining to fit a round well.

Here at
Imponderables Central,
the entire staff is unable to touch our toes without bending at our knobby knees. How can the human pretzels that perform for Cirque du Soleil place their legs behind their heads and play “Chopsticks” with their toes?

Medical authorities are quick to assert that flexible people have no more joints than mere mortals. As Timothy N. Taft, director of sports medicine at the University of North Carolina at Chapel Hill, wrote us:

Taft portrays hypermobility as more of a curse than blessing; orthopedists are far more likely to see patients complaining about this condition than bragging about their flexibility. Several genetic conditions lead to hypermobility, most commonly Ehlers-Danlos syndrome, an inherited condition in which the collagen (the protein that reinforces the structure of the joints) is hyperelastic. Those with Ehlers-Danlos syndrome often have other unpleasant side symptoms, including joint pain, osteoarthritis, and stretchable skin — the so-called rubber men in circus sideshows usually have Ehlers-Danlos.

Collagen is the key component in cartilage, which provides padding between bones. The more flexible your cartilage is, the more flexible you will tend to be. Children’s cartilage is especially elastic, which is why pre-adolescent boys and girls are capable of twisting and folding their limbs in gymnastics; as we age and hormones kick in, the cartilage hardens along with bones, and most of us lose flexibility.

The majority of people that we might offhandedly call “double-jointed” do not suffer from any medical condition. They most likely possess supple collagen and proportionately longer discs than the vertebrae they separate. Shallow sockets, smoother bone ends, and especially flexible ligaments also can contribute to hypermobility. Needless to say, regimens of stretching will enhance a predisposition toward flexibility.

Even if “double-jointed” is a misnomer anatomically, some partisans have embraced the term. The Web site of the Halston Gymnastic Club has a “Double Jointed Page” (http://www.hgc.mcmail.com/) that argues that the
Oxford English Dictionary
endorses the concept (the fifth definition of “double” in the
Shorter Oxford English Dictionary
is: “Fold…so as to bring the two parts into contact, parallel; bend (the body), especially into a stooping or curled-up posture….”). The site disdains the use of “hypermobility” because the prefix “hyper” is used to signify “too much.”

Ironically, while the general population is striving to become more flexible, the “double-jointed” often don’t take advantage of their attributes:

To folks with serious genetic hypermobility, extreme flexibility isn’t necessarily a gift, as their full range of motion sometimes sends their bones and ligaments to places that joints were not meant to support, while others derive a paycheck from their “double-jointedness.”