Mary Sue Yates, age 13, of Columbia, .C., for her question:

Does a pigeon really give milk?

Baby pigeons are fed on a formula called pigeons milk. Actually this food is not like cows milk. For only the mammals are able to produce this type of mother's milk. In fact, the ability to produce mothers milk distinguishes the mammals from all other creatures.

Pigeons milk is produced in the crops of the parent pigeon. It is food they have eaten and partly digested ‑ just right for Junior's sensitive young insides. The formula is a mushy half‑liquid.

Junior is waiting for dinner when either Mama or Papa fly back to the nest. Either parent can feed him. The grown‑up bird opens his or her mouth wide. The little bird reaches up and digs down inside. The parent bird bends over in an effort to pour the formula down Junior's hungry little gullet.

As Junior grows he struggles harder for his pigeon's milk. He beats his wings as he digs for his food. This exercise prepares him for the day when he will start his flying lessons. His parents will continue the pigeons milk formula until the youngster is able to fly off and gather crumbs and peanuts for himself.