Summary # 10 (How species change over time)

The differences between size and shape are called variation. Variation is the difference in appearance of inherited traits among the members of a species. An animal that blends with the colorof its surrounding may live longer that one with color that does not blend as well. This ability to blend with the envirment is called adaptation. An adaptation is a variation that increase's an organism chance for survival. There are two main theories that are used to explain adaptation the Jean-Baptiste Lamark theory and the Charles Darwin theory. Charles Darwin also suggested the natural section theory to explain why there is such a great variety of living organism on Earth. This theory divides into four parts : 1. Living thiings produce more young that can survive in the enviroment. 2. There is always a variation among offspring. 3. Some variations in traits enable members of a species to survive and reproduce more succesfully than others. 4. Natural selection is always taking place. Competition is the struggle among living things to obtain the resources they need to survive.
Completely new variations are taken place in offsprings  by mutation.