Vestigial Structures: Evolution's Fallacies Jake Drahos Many people have never heard of vestigial structures, but do in fact know what they are. Vestigial structures are, simply put, useless. These are things like the appendix or tailbone; evolutionary leftovers from an organism's ancestors. Examples of Vestigial Structures Vestigial structures are everywhere. Humans have quite a few. The appendix is the poster child of vestigial structures; it's purpose long lost in the antiquities of The Appendix evolution. The tail bone is a remnant of a very essential structure for Unlike most other vestigial structures, the human our ancestors. Wisdom teeth, male breast tissue, and the muscles for appendix can potentially be harmful. In a condition known wiggling our ears join the list of useless traits. Even the little toe as appendicitis, the appendix becomes inflamed. Without could be considered vestigial. However, other treatment, it will burst, filling the torso with bacteria and and animals exhibit vestigial structures as well. intestinal contents, a potentially lethal situation. Manatees have nails on the ends of their flippers, (Johnson ) which evolved from the legs of land mammals. Boa constrictors even have hip bones and the remnants of back legs (Johnson). While neither of these features provide any benefit to the organism, they still exist as remnants of a past ancestor. Why do Vestigial Structures Exist? Vestigiality is a natural and logical side effect of natural selection. Vestigial structures neither benefit nor harm the organism, and, as a result, are untouched by natural selection. At one point in the evolutionary history of an organism, the structure had a purpose. As evolution progressed, it lost that purpose. This is far from a reason for the structure to disappear, as an organism lacking the structure in question is no more likely to reproduce than one still holding on to it. If the lack of a certain structure is not particularly beneficial, then there is no reason for it to disappear as a result of evolution. What does no harm need not go away. Yet a Use Exists While vestigial structures are, by definition, useless, at least to the organism on which they exist. However, they do have a use. Vestigial structures can help determine the evolutionary relationships between organisms. Two organisms may share a vestigial structure. This likely means they shared a common ancestor. A vestigial structure can be even more informational. If a structure has a use in an ancient species, and an identical yet vestigial structure exists in a modern species, the ancient one is likely an ancestor of the modern species. The structure began useful, but lost use over time. Vestigial structures, useless by definition, are, in fact, incredibly useful at determining evolutionary relationships. Works Cited "Appendicitis - PubMed Health." Web. 01 June 2011. <http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001302/>. Covey, Jon A. "Vestigial Organs." Welcome to the South Bay Creation Science Association Web Site. Web. 23 May 2011. <http://www.creationinthecrossfire.com/Articles/VestigialOrgans.html>. Johnson, George. "Evidence for Evolution (Page 12)." Txtwriter Inc. Homepage. Web. 23 May 2011. <http://www.txtwriter.com/backgrounders/Evolution/EVpage12.html>. "Top 10 Useless Limbs (and Other Vestigial Organs) | LiveScience." Current News on Space, Animals, Technology, Health, Environment, Culture and History | LiveScience. Web. 23 May 2011. <http://www.livescience.com/11317-top-10-useless-limbs-vestigial-organs.html>.
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