Kevin James McCawley, age 14, of St. Paul, Minnesota, for his question:

How did early man discover which foods were edible?

This is where those who insist that people are no different from animals fall flat on their opinionated noses. Almost all the animals are born with built¬ in diet instructions that automatically warn them of unsuitable foods. True, many animals can be fooled by poisoned bait. But even these unfortunate creatures know that the bait is their kind of food. Mankind has no built in automatic system of diet instructions. He thrives on a wide variety of plant and animal food and nature expects him to use his unique intelligence to make his own selections. He is equipped with sensitive taste buds to help him choose a pleasing menu. He has an internal mechanism that gives painful prods when a meal is hard to digest.

This internal defense mechanism may reject food that is mildly poisonous and throw it up. But it fails to cope with fierce, fast acting poisons. Our early an¬cestors had to deal with this handicap by trial and error. When hungry, they sampled all kinds of strange foods and learned, often by harrowing experience, to select the suitable and avoid the unsuitable. They imparted their food testing information to their children. Through the ages mankind has garnered a body of wisdom concerning edible and inedible foods and his sensible offspring abide by it.