Toby Thiersch, age 9, of West Vancouver, B.C., Canada, for his question:   

 What does an ameba eat?

The ameba is not a fussy eater and almost anything will do for his dinner. However, his food must be served in very small helpings. This is because he is a very small single celled animal. He is too small for our eyes to see. His helpings of meat and vegetables must be even smaller. He lives in water or drops of moisture, so some of his food comes floating by and some is down below in the mud. His favorite vegetables are tiny algae. Most of them are green, though some are bluish green and some are reddish brown. He also devours other single celled animals    that is if he can find any that are smaller than he is. Sometimes he dines on miniature bacteria. And he often helps himself to a speck of rotting meat or waterweed. These scraps float around when plants and animals decay in the water.