Natural and Sexual Selection
One of the first mechanisms proposed by Charles Darwin was natural selection. Some may refer to this as "survival of the fittest," whereby species that produce offspring have been successful in doing so because they have produced random individual features which have lead them to live longer and pro-create offspring with the same inheritable desired features. Therefore, different desired traits are passed down through generation-to-generation, and those traits which are not so popular will eventually die out. Darwin also proposed a second which tied into the process of natural selection it is sexual selection.
Natural selection is considered to be the biggest factor in differences in species and their genomes. When Darwin was observing wildlife in the Galapagos Islands he claimed that the finches had a curious patter of adaptation. A major drought hit the islands which caused the plants to produce fewer seeds. They learned three things from this drought and examining the behaviors of the birds. The first thing being that the supply of food was not sufficient for the entire population and many of the finches didn’t survive. The second thing was the beak depth varied among the birds on the island and aided their survival. During the drought the birds finished off all the small birds leaving behind only the large hard ones. The small beak birds weren’t able to survive with their small beaks and the large seeds. The last thing was that parents and their offspring has similar beak depths. After all of this they discovered that through natural selection an organisms shape, size and compositions were adapted to better their survival in their environment. (Boyd and Silk, 2006: 7-9)
Sexual selection is separated into to different forms intrasexual and intersexual. Intrasexual is competition among individual of the same sex in a population whereas intersexual is where only one sex can control the reproductive access by choosing among...