Christine Velis, age 10, of Salt Lake City, Utah, for her question:

How many 1ands of birds are there?

We know that there are at least 9,000 different birds, though some are rarely seen. This is the number of bird species, however, some members of the same species may near slightly different colors. For example, our red breasted robins on this continent all belong to the same species. But some have smaller red vests than others, or perhaps more speckles under their chins. These types are called varieties of the same species. We cannot count them as different birds because they can mate and have babies. Different species cannot do this.

The tiny hammer can nest in half an egg shell, the ocean going albatross can spread his wings 12 feet wide. The mighty ostrich stands seven feet tall    but he cannot fly at all. There are gaudy parrots and little brown wrens that match the brown earth. There are sinkers, chirpers and squawkers. But all the 9,000 species wear feathers of some sort and all have wings, even though some do not fly. And all birds lay eggs.