Safe, by a Hair!

If you have trouble with cockroaches, pity the toad. That sticky-tongued creature feeds on roaches, snagging them with a lightning quick flick of the tongue. The problem is that, more often than not, the cockroaches get away. How do they do it?

According to an article in the December 1980 issue of “Scientific American,” the roach does not need to see or hear the toad in order to escape his ambush. Instead, the insect has very sensitive hairs at its rear end that detect air movement. As the toad lunges for the roach, a puff of air, disturbed by the movement, reaches the roach first. The air moves these little hairs and, somewhere inside the cockroach, an alarm sounds. Less than a 20th of a second later, the roach is off and running.

How does it know which way to run? The tiny hairs are not all sensitive to wind coming from the same direction. If the attacking tongue comes from behind rather than from the side, different hairs are stimulated. The nervous system of the cockroach, like a microcomputer, analyzes data from the stimulated hairs and decides which way the wind is blowing. Then the insect runs away from the source of the wind​—all in a flash.

Scientists marvel at the computing skills of the humble cockroach. We, too, marvel​—at the engineering ability of the Creator.