What must happen for evolution to occur?
Evolution results from natural selection. Occasionally a gene mutates or a characteristic is better for the environment (survival of the fittest). If it turns out to be for the better then the organism with that characteristic will be more desirable then it will survive/ be more attractive to mate with therefore the mutation is passed on to more. If it isn’t advantageous then the organism is killed off/ is not considered good for mating with. Gradually this gene is passed on to every on of the species via natural selection. Example: giraffes with long necks. Originally had shorted necks. The ones who had the longest necks, could reach more food. These giraffes thrived while the shorter necked ones died. Only the long neck genes are passed on. Result only long necked giraffes remain today. black/white moth species. Originally in this species the white moth was abundant and the black moth was the mutation. However during the industrial movement changed the environment, blackening the tre
