When Do Fish Sleep? (20 page)
Why
Is There an Expiration Date on Sour Cream? What’s the Matter, Is It Going to Get More Sour?
We’ve gotten this Imponderable quite often on radio interviews, usually from smug callers sure that expiration dates are a capitalist plot to force us to throw away barely used sour cream. But mark our words: if you think sour cream is tart when you open it, just leave it in the refrigerator too long and taste the difference. As the expiration date on sour cream becomes a dim memory, bacteria acts upon the sour cream, making it unbearably tart. Given enough time, mold will form on the sour cream, even if it is properly refrigerated.
Sour cream has about a month-long life in the refrigerator. Wait much longer and we’ll bet that you won’t want to test just how sour cream can get. If you think we’re wrong, there’s one way to find out for sure.
Go ahead and taste it. Make our day.
If the United States Postal Service has problems sending a letter across town in a few days, we wondered how they contended with a letter sent to Nebraska from a remote village in Egypt. Does every post office hire a staff of linguists to pore over mail and route it in the right direction?
No, not every post office. But the USPS does employ linguists at their International Exchange Offices, located at the major ports (New York, San Francisco, Miami, and Boston) where foreign mail is received. All mail is separated and sorted at these border points and sent on its merry way.
We contacted some foreign consulates to find out how they solved the problem of indecipherable mail. A representative of the Greek consulate told
Imponderables
that if foreign mail is written in one of the international languages, multilingual personnel have no problem sorting it. If no postal worker can translate an address, the postal service will likely do what we did—call the embassy or consulate of the country of the sender and hope for the best.
Submitted by Charles F. Myers of Los Altos, California
.
Why
Do Roaches Always Die on Their Backs?
We couldn’t believe that three readers actually had experienced the good fortune to see a dead roach and had torn themselves away from the subsequent celebration long enough to note the posture of the deceased insect. But we trudged on nevertheless, contacting entomologists who actually get paid to study stuff like this.
Professor Mary H. Ross, affiliated with Virginia Polytechnic Institute and State University, told
Imponderables
that when a roach dies, its legs stiffen and the cockroach falls on its side. Because most roaches have a flattened body form with narrow sides, the momentum of the fall rolls them onto their backs.
John J. Suarez, technical manager of the National Pest Control Association, adds that small cockroaches, such as the German and the brown-banded, are more likely to die on their backs. Larger cockroaches with lower centers of gravity, such as the American and the Oriental, occasionally die face down.
Needless to say, we can’t guarantee the position of dead roaches contained in traps. Maybe the lifeless occupants of Roach Motels lie perfectly prone. Unfortunately, there is only one way to find out and only entomologists have the stomach for it. Please don’t try to verify this at home!
Submitted by Gloria Stiefel of Orange Park, Florida. Thanks also to Irma Keat of Somers, New York; and Gregg Hoover of Morgan Hill, California
.
Why
Does Warmth Alleviate Pain?
A caller on Tom Snyder’s radio show posed this Imponderable. We had no idea of the answer, but it was surprising that so many physicians we spoke to didn’t know the answer either.
We finally got the solution from Daniel N. Hooker, Ph.D., coordinator of Physical Therapy/Athletic Training at the University of North Carolina at Chapel Hill. His answer included plenty of expressions like “receptors,” “external stimuli,” and “pain sensors.” So let’s use an analogy to simplify Hooker’s explanation.
If a pneumatic drill is making a ruckus outside your window, you have a few choices. One is to do nothing, which won’t accomplish much until the drill stops. But another option is to go to your stereo and put on a Led Zeppelin record at full blast. The pneumatic drill is still just as loud—you may still even be able to hear it. But the music will certainly distract you (and for that matter, your next-door neighbors as well), so the drilling doesn’t seem as loud.
Hooker emphasizes that most of us associate warmth with pleasant experiences from our youth. By placing heat on the part of our body that hurts we stimulate the sensory receptors, which tell our brain that there has been a temperature change. This doesn’t eliminate the pain, but the distraction makes us less aware of the pain. As our body accommodates to the high temperature, we need fresh doses of warmth to dampen the pain. When we receive the renewed heat treatment, we
expect
to feel better, so we do.
Why
Can’t We Use Both Sides of a Videotape like We Do with an Audio Tape?
Don French, chief engineer of Radio Shack, is getting a little testy with us: “If you keep using me as a consultant on your books, we are going to have to start charging for my service!”
We have read all of the bestselling business management books. They all reiterate that most people aren’t motivated by higher pay but by recognition of their effort and accomplishments. So to you, Don French, we want to acknowledge our heartfelt appreciation for the efforts you have expended in educating the American public on the wonders and intricacies of modern technology in our contemporary culture of today. Through your efforts, our citizens will be better equipped to handle the challenges and complexities of the future.
But not one penny, bub.
Luckily, Mr. French couldn’t resist answering this Imponderable anyway.
It turns out that even though some audio cassette recorders require the tape to be flipped before recording on the other side, the recorder doesn’t actually copy on both sides of the tape. It copies on the top side of the tape in one direction and the bottom in the other direction.
On videotapes, the audio is also recorded on a small portion of the top side of the tape. But the video, with a much higher frequency requirement and slower recording speed, needs much more room to copy, and is recorded diagonally on most of the remaining blank tape.
Submitted by Jae Hoon Chung of Demarest, New Jersey
.
Why
Are the Toilet Seats in Public Restrooms Usually Split Open in the Front?
This has become one of our most frequently asked Imponderables on radio shows. So for the sake of science and to allay the anxiety of unspoken millions, here’s the, pardon the expression, poop on a mystery whose answer we thought was obvious.
Try as they might, even the most conscientious janitors and bathroom attendants know it is impossible to keep a multiuser public toilet stall in topnotch sanitary condition. Let’s face it. Pigs could probably win a slander suit from humans for our comparing our bathroom manners to theirs. Too many people leave traces of urine on top of toilet seats. Men, because of a rather important physiological distinction from women, particularly tend not to be ideally hygienic urinators, but most sanitary codes make it mandatory that both male and female toilets contain “open-front” toilet seats in public restrooms. In fact, at one time, “open-back” seats were mandated as well, but the public wouldn’t stand (or sit) for them.
If they are more hygienic, why not use open-front toilet seats at home? The answer is psychological rather than practical. An open-front seat would imply to the world that one’s bathroom habits were as crass as those employed by the riffraff who use public restrooms. Still, we would think that open-front toilet seats in home bathrooms might lessen the number of divorce-causing arguments about men keeping the toilet seats up.
Submitted by Janet and James Bennett of Golden, Colorado. Thanks also to Tom Emig of St. Charles, Missouri; Kate McNeive of Scottsdale, Arizona; and Tina Litsey of Kansas City, Missouri
.
How
Are the First Days of Winter and Summer Chosen?
This Imponderable was posed by a caller on John Dayle’s radio show in Cleveland, Ohio. John and the supposed Master of Imponderability looked at each other with blank expressions. Neither one of us had the slightest idea what the answer was. What did it signify?
We received a wonderful answer from Jeff Kanipe, an associate editor at
Astronomy
. His answer is complicated but clear, clearer than we could rephrase. So Jeff generously has consented to let us quote him in full:
The first day of winter and summer depend on when the sun reaches its greatest angular distance north and south of the celestial equator.
Imagine for a moment that the Earth is reduced to a tiny ball floating in the middle of a transparent sphere and that we’re on the “outside” looking in. This sphere, upon which the stars seem fixed and around which the moon, planets, and sun seem to move, is called the celestial sphere. If we simply extend the earth’s equator to the celestial sphere it forms a great circle in the sky: the celestial equator.
Now imagine that you’re back on the Earth looking out toward the celestial sphere. You can almost visualize the celestial equator against the sky. It forms a great arc that rises above the eastern horizon, extends above the southern horizon, and bends back down to the western horizon.
But the sun doesn’t move along the celestial equator. If it did, we’d have one eternal season. Rather, the seasons are caused because the Earth’s pole is tilted slightly over 23 degrees from the “straight up” position in the plane of the solar system. Thus, for several months,
one hemisphere tilts toward the sun while the other tilts away
. The sun’s apparent annual path in the sky forms yet another great circle in the sky called the ecliptic, which, not surprisingly, is inclined a little over 23 degrees to the celestial equator.
Motions in the solar system run like clockwork. Astronomers can easily predict (to the minute and second!) when the sun will reach its greatest angular distance north of the celestial equator. This day usually occurs about June 21. If you live in the Northern Hemisphere and note the sun’s position at noon on this day, you’ll see that it’s very high in the sky because it’s as far north as it will go. The days are longer and the nights are shorter in the Northern Hemisphere. The sun is thus higher in the sky with respect to our horizon, and remains above the horizon for a longer period than it does during the winter months. Conditions are reversed in the Southern Hemisphere: short days, long nights. It’s winter there.
Just reverse the conditions on December 22. In the Northern Hemisphere, the sun has moved as far south as it will go. The days are short, while the lucky folks in the Southern Hemisphere are basking in the long, hot, sunny days.
The first days of spring and fall mark the vernal and autum nal equinox, when the sun crosses the equator traveling north and south. As astronomer Alan M. MacRobert points out, the seasonal divisions are rather arbitrary: