Sherman McLaughlin, age 8, of Sandston, Virginia, for his question:

How do birds find worms?

A robin has his breakfast early, very early in the morning. The early bird is more likely to catch a worm because worms go down to bed when the sun comes up. Some people say that a robin can hear the soft rustle of a moving worm. Some say he puts his beak close to the ground to smell for worms. Some say his bright eyes stare down to spot a pink worm in the grass. For a long time the real experts were not sure how a clever robin finds a worm.

Many people wonder about this question and now at last we seem to have the answer. For one thing, we are sure that a robin cannot smell out a worm in the ground. His nos¬trils are two small holes in his beak. But the sniffer inside his nose is not very food and he cannot smell much of anything. When he hunts for his early breakfast, he hops a few jerky hops, then stops and cocks his little head to one side. He seems to be listen¬ing with his ear fairly close to the ground. But where is his ear?

Actually a bird’s ears are just where you would expect them to be    one on each side of his head. But he has no outer ears. His ears are inside his head. The openings are covered with skin and feathers. The real work is done by inner ears and a robin can hear very well. Maybe his hidden ears are sharp enough to hear all sorts of soft rus¬tlings in the grass. But actually he does not cock his head to listen for worms crawling on or under the ground.

Notice those bright little eyes of his. Your eyes are side by side, facing front. Both of them see the same view. A robin’s eyes are placed on opposite sides of his feathery head. He has two different views, one on each side. Each eye sees a round view    and the two round windows meet and cross over in front of his beak. In this small cross over section, both eyes see the same view and this is where he sees the best. But he has to keep turning his head to focus on this narrow section of the view. This is why he cocks his head.

So when worm hunting, he hops a few steps, stops and cocks his head. He is focusing his eyes on a certain small piece of the ground    peering for a worm. If he sees no worm, he hops a few more jerky hops and stops for another good look. After many tries he may spot a juicy worm, crawling home to hide in his burrow all day. Or he may see just the end of a worm, peeping out from a burrow. Then a tug of war begins. The robin grabs the end of the worm in his beak    and pulls. But the worm pulls too and he can pull quite hard, though usually the robin wins. Sometimes the worm gets pulled in two pieces and the robin gets only half. The other half is left down in the burrow. And, of all things, sometimes this half a worm manages to regrow himself and become a full ¬sized worm again.

A robin is always famished because he keeps so very busy. He would like to eat 60 worms a day, if he could catch that many. He never does. So through the rest of the day he snacks on berries and fruit. Very early next morning, he goes hunting again in the dewy grass. This is the most likely time and the most likely place to find worms.