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									                                 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.

       <>. Covey, Jon A. "Vestigial

       Organs." Welcome to the South Bay Creation Science Association Web Site. Web. 23 May 2011.


Johnson, George. "Evidence for Evolution (Page 12)." Txtwriter Inc. Homepage. Web. 23 May 2011.


"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.

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