Kam Wing Chong, age 11, of Montreal, Quebec, Canada, for her question:

WHICH IS THE SMALLEST MAMMAL?

This furry little fellow is about as big as your little finger  and he tries very hard to keep out of sight. But like all of nature's small children, he has important work to do in the world. He rids the soil of pesky grubs and bugs that prey on the roots of plants. So even the smallest mammal has an important role in ecology.

You might mistake the smallest mammal for a teen age mouse, though he is not related to the mousy rodents. He is a

shrew, and his family tree goes way back to the days of the dinosaurs. When cornered, he is a scrappy little character. The rows of sharp teeth in his long snout are always eager to bite a finger. The bite may be poisonous, which makes him unpopular.    

The mousy looking shrew has musk glands that give off an unpleasant odor. Apparently his odor also gives him an unpleasant flavor. Cats and other mousers refuse to eat a shrew, though they hunt and catch him. No doubt his horrible smell has helped him to survive through the ages.

There are 170 shrew species and, apart from Australasia and the polar regions, they are at home almost everywhere. There are white toothed and red toothed species. The largest types are bigger than mice. The smallest is the pygmy shrew; he is about 2 inches long, with a 1 inch tail, and weighs no more than a dime. He is the smallest of all the mammals.

Like other shrews, he lives a rather solitary life ¬though there may be thousands of his kinfolk in a meadow. In the animal world, energy is related to the area of body surface. Smaller animals have a relatively large surface, so they need more food to keep going. The small shrew is so famished that he cannot live through the night without a meal.

He solves this problem by dividing day and night into three hour periods for resting and eating. He will eat almost anything, including seeds and meat. But his favorite menu consists of grubs and bugs.

The female shrew builds a ball shape nest of leaves and grasses and usually bears two litters during the summer. The four to 10 babes are blind and helpless, and each one weighs about half a gram. Being mammals, they feed on mother's milk. In less than a month they are ready to leave home. The nervous, famished shrews become old and worn out after only about 15 months.