About 3.5 billion years ago the earth's environment was very different than it is today. There was not a significant amount of free oxygen in the atmosphere. According ("Evolution," Microsoft® Encarta® Encyclopedia 99. © 1993-1998 Microsoft Corporation) experiments have shown that complicated organic mol

By the 1880s in the Manchester, England, area, gases and soot were killing the light-colored lichens on the trees and caused the trees to become even darker. The change from light to dark moths began to happen there also. The smoke and smog from the factories there also darkened the trunks of the trees where the moths rested. Therefore, the dark trees made the lighter moths easy for the birds to eat.

Natural Selection has been taking place for billions of years and changing the life on this planet. Survival of the fittest is still taking place today just on different terms. In 1858 when Charles Darwin and Alfred Wallace proposed these theories I wonder if they knew it would still be talked about now and in the future.

Before complex animal communities could develop, plants had first become established to support the animals. The small plant-eaters would then become the food of predators and scavengers. Land plants appeared about 400 million years ago by expanding out of lowland swamps. Some invertebrate groups followed them onto land. Vertebrates evolved from freshwater fish nearly 360 million years ago. Dinosaurs and mammals shared the environment for 135 million years, but only the mammals survived extinction.

Many other examples of variation within species could be cited. In south central Africa, the Pygmy and Masai tribes live not far from each other. One is the shortest group of people in existence today, the other, the tallest. Both are human beings, although only the height is different. Pigeon lovers tell us there are more color variations among pigeons than among any other animal or bird in the world. That is the result of only a couple centuries of intensive breeding by fanciers in Europe and America. In spite of the variations, they can all interbreed and are just pigeons.

Some say, as stated in Asimov’s New Guide of Science ARTICLE by Isaac Asimov, “There are many kinds of roses, finches, dogs, and horses—but all the roses, finches, dogs, and horses are just that; they never change into daisies, parrots, cats, or cows.” Non-believers argue that all the offspring produced in the plant and animal kingdom remain in the same species—the production of new creatures never occurs.

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