Robert J. Ordway, age 10, of Stittville, N.Y., for his question:

ARE BATS REALLY BLIND?

It would be nice if people liked to talk about the wondrous truths of the animal world. But for reasons unknown, they usually prefer to spread senseless bits of gossip. For example, each generation of human children learns that cats have nine lives, elephants are scared of mice and bats are blind. None of these rumors is true.

The furry little bats are creatures of the night. Often they fly forth in squadrons just after the sun goes down to catch pesky gnats on the wing. Their little bright eyes see just about as well as ours do in the dim, dusky light.

We share our world with at least 2,000 different bats. And there is evidence that at least some species see quite well in the bright light of day. Most likely all of them see better in the dark than we do because they are more used to dim caves and hollow trees. But none of them can see in total darkness and, so far as we know, no bat has our glorious gift of color vision.

However, the little brown bats have a remarkable gift that we do not. Long before the human family arrived on the planet earth, the bats were using radar to find their way from here to there. Radar uses sound waves that bounce back from solid objects, bringing  echoes.

Human ears can hear sounds that reach only so high. Bats can hear sounds that go much higher, into the supersonic range that we cannot hear. Their high pitched voices also utter sounds in the supersonic range. A bat’s built in radar system works by sending supersonic twitters that echo back from solid objects to his supersensitive ears.

To us he seems to fly through the dusky darkness in complete silence. Actually he is uttering supersonic twitters from his wide open mouth. These sound waves bounce off twigs and other solid obstacles in his path. His sensitive ears catch the echoes, and his furry wings swerve in time to avoid collisions.

Even if the bat had keen eyesight, it would not help him to see inside a pitch black cave or outdoors on a dark night. But his remarkable built in radar system works in daylight and in total darkness. As he utters his supersonic cries and hears their supersonic echoes, he forms a sound picture of his surrounding—very much like the man made radar system on a plane or ship.