The Surprising Origins of Life's Complexity

Article:

Zimmer, Carl . "The Surprising Origins of Life's Complexity." Scientific AmericanAug. 2013: 84-89. Print.

            Out of the many theories of evolution, Darwin’s theory of natural selection is one of the most supported theories of evolution today. Darwin’s theory, in simple words, is the passing down of traits that help a species survive in the wild. For example, birds with long beaks survived because they were able to get more food, than birds of the same species with shorter beaks. Just as organisms can evolve, so can their complexity, from a simple origin to a complex being.

            The definition of complexity in organisms is considered to be a vast variety of different building blocks. For example, our bodies are made up of 100 trillion cells, each of those cells are different. Therefore, we can say that we are more complex than other animals, like sponges. Complexity increases as time goes by, either developing into useful traits, or causing a bad mutation. Natural selection does its job here, passing down useful traits, but also preventing useless mutations from continuing, therefore only slightly increasing the levels of complexity. This has caused many scientists such as Daniel W. McShea and Robert N. Brandon to believe that complexity can increase in the absence of natural selection.

            McShea and Leonore Fleming observed fruit flies that lived and bred in laboratories. According to the zero-force evolutionary law, these flies would be more complex than wild ones, because natural selection would not stop mutations from passing down. Their hypothesis turned out to be true, and the experiment supported the law. However, there are many critics suggesting that adult flies that died from mutations in the lab before, were not taken into account.

            Another theory suggests that some genes evolved neutrally or the constructive neutral evolution. In other words, the evolution of these genes does not have any effect on the organism. For example, the genes Vma11, present only in fungi, and the gene Vma3, in animals and fungi, have the common ancestor gene called Anc.3-11. Somewhere during evolution this gene must have split in two; an experiment shows that when Vma3 and Vma11 were removed in yeast and replaced with Anc.3-11, the yeast was still able to function fine. Other examples of neutral evolution include the development of the RNA-editing enzyme.

            These discoveries are important in the field of science because it encourages scientists to look beyond the current theories and try to develop their own. We can also learn how environment affects the evolution of animals. Similar to the fruit flies, humans in 1^st world countries are being fed and sheltered from the harms of nature, most of us don’t have to hunt or run away from predators for survival. Therefore could the development of non-nomadic people be different from that of nomads in Africa. If the same development were to occur in humans, as in what happened to fruit flies, could mutations develop making us more complex than those exposed to nature more. Ideas such as this can be developed based off the works of McShea, Brandon, Fleming and other scientists. In addition to scientific purposes, this article can let others understand and know more about evolution, complexity and how organisms are affected by these. 

            I thought this article was interesting and fascinating. It was not too long, and even with my basic knowledge of biology I was able to understand everything that was written. I especially liked how after every experiment the author, Carl Zimmer, described, added in the opinion of critics and facts that helped condemn the results of experiments. However, I wish there was more written on the experiments done on fruit flies. Zimmer does explain the results, hypothesis, and there is even a picture in the beginning of the article showing the differences of fruit flies, but I still wished there was more about the process of the experiment because it was interesting. This article would be more appealing if there was more emphasis on how this topic affects human life.