In the book "Survival of the Sickest," Dr. Moalem discusses the various examples of consequences of natural selection. The many parasites which are represented in Chapter 5, pages 95 - 111 are the examples of the results of natural selection that promoted to develop ways to spread their offsprings. He additionally introduces the idea of transposons, the genes that can move along the chromosomes into random loci. Significance of this discovery is that this can explain one of the greatest mystery of Darwin's theory and thus can reinforce his theory; transposons can accelerate the mutation rate since it will directly change the genetic code and it is directed by the organisms, not by the environmental factors. In addition, the rate of movement of transposons increases as the environment becomes harsh for the corns. This is well-explained in the Chapter 6 page 137 and Dr. Moalem explains as the great solution to the obstacles Darwinism used to face. However, I believe that this is not a ultimate solution since transposons only occur in the eukaryotic cells. therefore, if we discuss the evolutionary history of living organisms, we still have to rely on the explanation about random mutation which is directed by natural cause, and there are theory that confirms that the gene selection and microevolution that occurs in genetic level can be totally random, thus the adaptive values might not matter to the evolutions (for more info., please follow this link: http://www.nature.com/scitable/topicpage/neutral-theory-the-null-hypothesis-of-molecular-839).
According to these details and even your knowledge obtained from class materials form Evolution Unit and Big Idea 1 about evolutionary history and its significance, How would you feel which influences more to the evolution of living organisms; random chances, or the adaptivity and adaptive values suggested by Darwin.
Makoto Seita e-mail (mseita3@students.d125.org)
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