Jerry Gellerstein, age 12, of Bronx. N. Y., for his question:

Are there birds with teeth?

Not for sixty million years has any bird had a toothache or needed a dentist. Teeth have been absolutely out of style in the bird world for that length of time. Before then, toothache must have been quite common in the world of birds. For the early birds that lived on earth had mouths jam‑packed with teeth.

Birds began to separate from the lizard family about 125 million years ago, We have an early fossil of one of these first flyers. Not only did this fellow have a mouth full of teeth, he had claws on his wings.

Birds took their present‑day form about 60 million years ago. By then they had developed warm blood, They gave up teeth and the claws on their wings, but have changed very little since.