Natural selection is the cornerstone of evolution. In the process of natural selection, individuals in a population who are well-adapted to a particular set of environmental conditions have an advantage over those who are not so well adapted. The advantage comes in the form of survival and reproductive success. For example, those individuals who are better able to find and use a food resource will, on average, live longer and produce more offspring than those who are less successful at finding food. Inherited traits that increase individuals' fitness are then passed to their offspring, thus giving the offspring the same advantages.
Aquired mutations are caused by radiation, viruses, transposons and mutagenic chemicals, these changes cannot be passed onto the next generation. A new mutation is an alteration in a gene that is present for the first time in one family member as a result of a mutation in a germ cell (egg or sperm) of one of the parents or in the fertilized egg itself, this can be passed on to offspring. Another form of genetic mutation is
meosis which is a special type of cell division necessary for sexual reproduction. If
Independent Assortment or
genetic mutation create beneficial alleles, the result would be a better species more able to survive. On the other hand, detrimental changes in DNA would result in a species with a lower chance of survival. An
allele is one of two or more forms of the DNA sequence of a particular gene. Each gene can have different alleles. Sometimes, different DNA sequences (alleles) can result in different traits, such as color. Other times, different alleles will have the same result in the expression of a gene.