Free ride: Tailgaters in line for speed


 Q. How are birds, fish, and race car drivers on to the same traveling trick? -Nemo

A. They're all tailgaters, hitching something of a free ride in the wake of the leaders, says Cleveland State University physicist Jearl Walker.

Birds flying in V-formation get added lift in the airstream of the forward birds. Fish swimming in schools can travel up to six times as far as solo. Race car drivers save fuel by riding the "slipstream" of the car in front, cutting air resistance.

A twist on this, porpoises may ride along effortlessly for hours ahead of ships' bows, surfing on waves emanating from the vessels. And small "pilot fish" will float in front of a shark's mouth– guiding it, legend has it– staying a fin's length ahead of dinnertime (the shark's) owing to the lucky laws of physics.

Q. Stunning date, so you put on an easy listening tape with "I love to touch and be touched" subliminal messages hidden in the music. Will this impassion your night? –S. Savitch

A. It just might if you play it off right. While subliminal messages (below the threshold of perception) have little or no proven effect, test subjects when told they had been listening to such a tape tended to feel they were influenced, says Hope College psychologist David G. Myers.

This was true even when tapes were secretly switched: Subjects who were told they were listening to commercial tapes with memory enhancement messages implanted but who were actually listening to self-esteem improvement tapes felt their memories had been improved. And vice versa. Yet standard psychological tests showed no actual memory or self-esteem boosts in either case.

Here is a classic "placebo," suggesting would-be tape seductionists must at some point pretend to come clean– "Ma cherie, about that new music we were just listening to..."

Q. You see headlights approaching, but is it a big car or a little car, nearby or far away? You see paratroopers on the beach, but are they big soldiers or little ones? –H. Ford

A. The common denominator here is "size constancy"– a car as it moves closer forms a larger and larger image on your retinas, but you know not to conclude the car is getting bigger. But in the dark, you can be fooled into thinking that two fairly close-seeming headlights signify a big car far down the road, when it might actually be a small car bearing down on you– with tragic results.

Especially in poor lighting, distance and size are easily confused. Deliberate perceptual deception of this sort was on the minds of Allied troops during their invasion of Normandy during World War II, when in early-morning twilight two-foot-tall dummies of paratroopers were dropped up the beach a distance from the planned landing site, say Camille Wortman et al. in Psychology, 3rd Edition. "In the poor light and general confusion, the Germans thought the dummies were real paratroopers attacking from a substantial distance."

Q. Why are there so many sex jokes going around? –A. D. Clay

A. Freud believed that humor bribes the superego (moral sense) into accepting talk about the difficult subject of sex, says Bruce Katz, psychologist at the University of Sussex. But people feel few qualms over discussing sex today, and this hasn't slowed the joke mill.

"People laugh if two conditions are met (plus some others, like being in the right mood): a. They find something surprising b. But it still makes sense."

Take this old classic: A sadist and masochist marry, a seemingly perfect combo. Finally, on their wedding night, the masochist begs, "Now beat me, honey, beat me." The sadist's reply: "No."

With sex jokes, the mind is focused like on no other subject, the expectations run high, so the startle is very strong. Then comes the unifying insight, giving relief.

"In summary, humor itself mirrors the sex act in that it is the temporary unity of opposites. Of course, humor is easier to get than sex, although the pleasure is not as sweet."

Send Strange questions to brothers Bill and Rich at