Are Lobsters Ambidextrous?

by David Feldman

  Submitted by Howard Livingston of Arlington, Texas.

  There are many miniature dogs. Why aren’t there any miniature house cats?

  Our correspondent, Elizabeth Frenchman, quite rightly points out that there are legitimate breeds of dogs that resemble rodents more than canines. If poodles can be so easily downsized, why can’t Siamese or Oriental cats? If dogs can range in size between the pygmyesque Pekingese or a sausage-like Dachshund to a nearly three-foot-high Borzoi or a lineman-shaped Saint Bernard, why is the size variation so small in cats?

  According to Enid Bergstrom, editor of Dog World, the answer is in the genes. Bergstrom says that dogs are the most genetically variable mammals, the easiest to breed for desired characteristics. The genes of cats, on the other hand, are much less plastic. If you try to mix two different breeds of cats, the tendency is for the offspring to look like an Oriental tabby. Of course, as dog breeder Fred Lanting points out, domestic breeds are miniature cats of sorts, the descendants of the big cats found in zoos.

  Helen Cherry, of the Cat Fanciers Federation, told Imponderables that felines could be reduced somewhat in size by interbreeding small cats, but she, as well as all of the cat experts we spoke to, insisted that they had never heard of any interest expressed in trying to miniaturize cats. A representative of the American Cat Association remarked that a cat is small enough already.

  Cat associations and federations are conservative by nature. Helen Cherry predicted that miniature cats would not be allowed to register or show or be “acknowledged in any way.” It isn’t easy being small.

  Submitted by Elizabeth Frenchman of New York, New York.

  What is the meaning of the numbers inside the arrows of the triangle on recyclable plastics? And what do the letters below the triangle mean?

  Both the numbers and the letters signify the composition of the plastic used in bottles and other containers. Imagine the problems at recycling centers if workers were forced to judge, by eye, whether a bottle was made out of polypropylene or polyethylene terephthalate, to mention merely two of the hardest to spell plastics.

  So the Society of the Plastics Industry, Inc., developed a voluntary coding system for manufacturers to classify plastic containers according to their resin composition. The most common plastics received the lowest numbers. The letters are abbreviations of the dominant resin from which the container is made. If containers are made from more than one material, they are coded by the primary material:

  1

  =

  PET, or polyethylene terephthalate, used in plastic soda bottles

  2

  =

  HDPE, or high-density polyethylene, used in plastic milk and juice jugs

  3

  =

  V, or vinyl

  4

  =

  LDPE, or low-density polyethylene

  5

  =

  PP, or polypropylene

  6

  =

  PS, or polystyrene

  7

  =

  Other

  The use of the plastic container coding system is voluntary, and the manufacturer does not in any way guarantee that the product will be recyclable or that the resins in the container will be compatible with other containers that have the same code number.

  This disclaimer is necessary for several reasons. Virgin materials are manufactured for specific applications; not all polypropylene products, for example, can be blended successfully. In some cases, the intended application for the recycled product might be more demanding than its original use. And plastic, like any other material, can be contaminated by the contents of the container during its original use. We know we have a strong preference not to have the plastic containers recycled at some of the fast food joints where we have eaten.

  Submitted by Dave Hanlon of Aurora, Illinois.

  Why are there no public bathrooms in most supermarkets?

  After trying about ten different supermarket chains, we got one on-the-record response—from giant Kroger. Off the record, we got the same response from other stores as we received from Kroger’s customer relations representative, Ginger Rawe: “Restrooms have always been available for customers’ and employees’ use, while not always visible to the public.”

  What incentive do supermarkets have to make restrooms noticeable or to encourage their use? Shelf space is at a premium, and supermarkets already suffer from very low profit margins. And stores have no desire to encourage noncustomers off the street to use restrooms. Department stores have long made it a policy to locate their bathrooms in the most obscure nooks of their space. You may have to walk past some unopened cartons or some unpackaged meat, but you’ll find every supermarket has bathrooms. The next time nature calls, just ask a clerk—assuming you can find one. He or she will know how and where to find relief.

  Incidentally, supermarket bathrooms are coming out of the closet, so to speak. With the advent of food superstores and warehouse supermarkets, many chains are trying to keep customers inside the store as long as possible, and floor space isn’t quite as tight as in “regular” supermarkets. Some chains are making their bathrooms user-friendly by posting signs so that customers can actually find them. Now if they would just stock the bathrooms with paper towels instead of those infernal hand driers, we’d be content.

  Submitted by Michael Reuzenaar of Colorado Springs, Colorado. Thanks also to Jadon Welke of Hebron, Indiana.

  Why do babies blink less often than adults?

  Babies blink a lot less than adults—many babies blink only once or twice a minute. The purpose of blinking is to spread tears over the surface of the eyes. Adults vary widely in their blink frequency, and such exigencies and circumstances as corneal touching, irritation, drying, foreign matter entering the eye, and emotional distress or excitement can all cause the blinking rate to rise dramatically.

  Ophthalmologists we contacted are full of theories but not a definitive answer. James P. McCulley, of the Association of University Professors of Ophthalmology, points out that the nerve structure of the infant’s eye is much less well developed than its adult counterpart. Babies don’t even manufacture tears during their first month of birth, so they clearly seem immune to the pain of dry eyes that would afflict adults who don’t blink more often.

  Ophthalmologist Samuel Salamon, of the Cataract Eye Center of Cleveland, Ohio, muses over other possible explanations:

  It is puzzling to us as to why babies’ eyes don’t simply dry out. Of course, they don’t spend that much time with their eyes open and the tiny bit of mucus that the eyes manufacture is usually enough to keep the front surface of the eye, the cornea, moistened sufficiently.

  Babies probably do not need to blink as often as adults because their fissures are much smaller. That is, much less of their front eye surface is exposed to the environment both because of the shape of their skulls and because their eyelid openings are very small. Thus, the eyes dry out much more slowly, and need lubrication much less often.

  Some ophthalmologists we contacted also speculated that babies’ blinking rates may not be caused as much by emotional components as adults’ are. Perhaps, but any parent who has had a baby cry for hours for totally unexplained reasons may hesitate to believe that stress isn’t a major part of the infant’s ecosystem.

  Submitted by Julie Ann Jimenez of Houston, Texas.

  Why do your eyes hurt when you are tired?

  Why do couch potatoes have such a bad reputation? While lying on the sofa perusing an Archie comic book or studying the impact of television violence on children by viewing Bugs Bunny cartoons, they are actually exercising what ophthalmologist James P. McCulley, of the University of Texas Medical School, calls “among the most active muscles in the body.”

  Actually, your eyes contain three sets of muscle groups:

  Each eye has six extraocular muscles attached to the outside of the eyeball, which turn the eyes in all directions. The extraocular muscles must coordinate their mov
ements so that both eyes look in the same direction at the same time.

  The sphincter and dilatory muscles open or close the pupils, defining how much light is allowed into the eye.

  The ciliary muscles attach to the lens inside the eye. When these muscles contract or relax, they change the shape of the lens, altering its focus.

  Concentrated reading or close work provides a workout for these muscle groups strenuous enough to make Richard Simmons proud. Unfortunately, as in all aerobic programs, the saying “no pain, no gain” applies, as Winnipeg, Manitoba optometrist Steven Mintz explains:

  The human eye is designed so that, if perfectly formed, it will form a clear image on the retina (at the back of the eye) of any distant object without having to use any of the muscles. In order to see closer objects clearly, however, each set of muscles has to work. The extraocular muscles must turn each eye inward; the sphincter muscles must work to make the pupil smaller; and the ciliary muscles must contract to allow the lens to change to a shape that will produce a clearer image.

  This minimal muscular effort is significant in itself. However, no human eye is perfectly formed and these imperfections will increase the amount of effort required. For instance, people who are farsighted must exert more than the normal amount of effort on the part of the ciliary muscles. Many people have extraocular muscle imbalances that force them to work harder. Virtually every person, as [he or she] approaches or passes the age of forty, suffers from a stiffening of the lens inside the eye, which forces those ciliary muscles to work even harder. Reading under poor light (either too much or too little) will cause the sphincter and dilatory muscles to work excessively.

  Just like doing 100 pushups can cause the arm muscles to become pain [ed], so can the muscular effort…described above cause sore eyes. Add to this that after several hours of close work, all of your body’s muscles are going to be more fatigued, your level of tolerance or your pain threshold for sore eyes will be less than when you are fresh.

  Ophthalmologists we consulted speculated that much of the eye strain attributed to tiredness is in reality caused by dryness. Dr. Ronald Schachar, of the association for the Advancement of Ophthalmology, notes that when one is tired, the blink rate slows down and the eyes are not properly lubricated. Close work also slows down the blink rate. Eye specialists are finding that workers at computer visual display terminals experience decreased blinking. This is one reason most consultants recommend stepping away from VDTs at least once an hour. While most of us are more than happy to rest our muscles after doing a few pushups, we expose our eyes to a marathon just about every day.

  Submitted by Martin Nearl of Monsey, New York.

  Why does after-shave lotion have to sting? What causes the sting, and could it be replaced by a nonsting ingredient?

  What’s the stinging culprit? Demon alcohol. John Corbett, vice-president of technology at Clairol, elaborates:

  The reason that most after-shave lotions sting is that they contain a relatively high percentage of ethyl alcohol, which, coupled with the fact that the facial skin has been subject to abrasion by the process of shaving, sets up an ideal situation for eliciting the sensation of stinging. The importance of the abrasion contribution can be readily tested by applying after-shave lotion some hours after shaving—no stinging sensation will be observed.

  Corbett mentioned that there are nonstinging after-shave balms on the market, but “none have achieved significant popularity.” So why do men crave a little pain in the morning? Corbett offers a few possibilities: “Presumably men find the sting of after-shave products an aid to waking up and proof that something is happening—or, maybe, men are masochists at heart.”

  Irene L. Malbin, vice-president of public affairs at the Cosmetic, Toiletry, and Fragrance Association, told Imponderables that after-shave lotions are not merely repackaged colognes or perfumes. Some lotions contain cooling astringent ingredients to heal small nicks and cuts; others moisturize and smooth the skin. Unlike perfumes, the scent is formulated to “perform for a short time.”

  The alcohol in after-shave lotion that stings you also protects you—it acts as an antiseptic. Cosmetics companies won’t brag about this fact in ads, for if they do, the lotion will be classified as a drug. Cosmetics companies avoid the drug classification so that the product will not fall under the regulatory and marketing constraints for pharmaceuticals, which are far more rigorous than for cosmetics.

  Submitted by Dr. John Hardin of Greenfield, Indiana.

  Why do you often see tires on top of mobile homes in trailer parks?

  Our initial research wasn’t encouraging. Augie, at Sunset Trailer Park, in San Jose, California, insisted that someone was pulling our leg. He had never heard of putting tires on a trailer and thought it would be a bad idea—if the tire dented the roof, rust, and eventually a hole, would create a major repair job.

  We were disappointed when Jane Owens, at Western Trailer Park in San Jose, agreed with Augie that she hadn’t seen tires on the roofs of trailers in northern California. But, she added, “They put tires on the roof in Nevada, where it gets windy.”

  “Oh, no,” we thought, “don’t tell us that the tires are used to weigh down the trailers to keep them from blowing away during tornadoes?” We were assured not. Kay McKeown, who runs a trailer park in Battle Mountain, Nevada, explained that most mobile homes have tie-downs to keep the trailers in place during severe wind.

  The purpose of the tires on the roof, Kay and Jane agreed, is to kill the noise of wind and rain hitting the surface of the aluminum or tin roof. The tires deflect the pinging sound of rain; even better, the weight of the tires keeps the wind from making the roof pop in and out, the most annoying and sleep-destroying sound since the invention of the leaky faucet. One layer of tires does the job effectively, and the tires needn’t have new treads or high biases. Of course, some trailers boast shingled roofs—these don’t pop in and out, and don’t need tires atop them, but they tend to cost more.

  We never would have thought of the “prevent the roof popping” answer to this Imponderable, but as ignorant as we were, we still couldn’t resist challenging the trailer park mavens about why tires were chosen to kill the sound of falling rain or hail. Surely, the owners could have found a better tool for the purpose—a tire, after all, is almost as much hole as substance. While Jane Owens acknowledged that tires can’t cover the whole surface of the roof and are much more successful at solving the popping roof problem, they greatly soften the noise. And, she adds, some people place a tarp or plywood directly over the roof and then place the tires on top. The additional covering not only kills the sound but helps prevent corrosion of the metal roof.

  Submitted by Lynne Lichtenstein of Hickory, North Carolina.

  Why do cows stick their tongues up their nostrils?

  We were tempted to say, “Because they can!” But in our relentless quest for truth we asked several cattle experts about this unsightly habit. Our serious guess was that the tongue was the easiest way to lubricate the dreaded “dry nose” condition that we assumed plagued our bovine friends. Wrong. Cows stick their tongues up their nostrils for two distinct reasons.

  Cows have nasolabial glands located in the dermis (just under the epidermis of the skin) that produce a watery secretion that helps keep their noises moist. Cows and other ruminants use these secretions to digest their food, as Michael T. Smith, of the National Cattlemen’s Association, explains:

  They frequently thrust their muzzles into the feed and, during rumination, run their tongues into the nostril and over the muzzle, thus bringing the secretion into the mouth. The chemical properties of nasolabial secretions are similar to saliva and aid in the digestive process (e.g., swallowing, enzymatic activity, buffering of the rumen [the cow’s first stomach]).

  Smith adds that buffalo exhibit the same behavior as their bovine cousins.

  Cows frequently endure respiratory infections that involve involuntary nasal discharges, sometimes quite heavy. Dr. Harold Amstu
tz, of the American Association of Bovine Practitioners, told Imponderables that these discharges are quite irritating and need to be expelled. But “cows don’t have handkerchiefs or fingers.” So they use their tongues to remove the irritant instead.

  Submitted by Gena Stephenson of Bloomington, Illinois. Thanks also to Irvin Lush of Louisville, Kentucky.

  Why don’t banks return canceled checks in numerical order?

  They could, but it would take one additional step that would ultimately cost the consumer, as well as the banks, more money. Ann Walk, executive director of the National Independent Bank Equipment & Systems Association, explains:

  The average account has only twenty-eight checks per month, and the banks feel that the customer can sort these and save the banks time. If you will notice on your monthly statement, the checks are listed in numerical order for your convenience. This is done automatically by machine and not by hand, as sorting checks would be.

  Are the checks placed in your statements in random order? Not really. Banks send bank checks with your statement in the order they received them.