Evolution By Natural Selection Is A Theory Created By...

Hewitt 1 Kyle Hewitt Period 3 5/3/15 A World Full of Mutations We live in a world full of mutations. These mutations are sources of variation, and are essential to our survival. As generations of organisms progress, we develop mutations that help us to adapt to the world around us. This is called evolution. Evolution by natural selection is a theory created by Charles Darwin in which he states that organisms evolve over time and develop certain characteristics, and the beneficial characteristics are passed onto the organism’s offspring as to increase the organism’s ability to survive, reproduce, and compete for resources. Natural selection keeps the mutations that lead to an increase in Darwinian fitness, which is the ability to survive†¦show more content†¦The trait that is most beneficial is, quite literally, selected to be passed on to the offspring of the organism. There are two types of evolution: macroevolution and microevolution. Microevolution is a shift in allele frequency within a population, and Hewitt 2 macroevolution is speciation through changing alleles. Competition often leads to evolution by natural selection. This is because organisms compete for resources, and mutations that allow the organism to compete better for resources will be passed on to offspring so that future generations can continue to thrive. The requirements for evolution to occur are variation within the population of organisms, inheritance of traits, a high rate of population growth, and differential survival and reproduction. Variation and inheritance of traits are needed so that many mutations can be experienced by the organism, and so the beneficial mutations can be passed on to offspring. A high rate of population growth is needed because the more reproduction means the more passing on of mutations, which leads to a test of how different mutations are beneficial or detrimental to the organism. Differential survival and reproduction is important because it determines which organisms will survive an d reproduce by how adapted to their environment they are. This leads to a transfer of useful mutations and traits, rather than non-benefical ones. While mutations and adaptations are necessary to the survival of a species,