Robert Wiedersheim
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Robert Wiedersheim (1848 – 1932) was a German anatomist who is famous for publishing a list of 86 “vestigial organs” in 1893.
Already during his school years Wiedersheim showed an interest in botany and zoology. However, he was not a good student and barely passed the final examination. His initial academic advancement was slow, until in 1876 he became an anatomist at the Albert Ludwigs University of Freiburg where he taught until 1918. He became an expert in comparative anatomy and published a number of relevant textbooks. He also collected early photographies and documents of scientists of his days.
In 1893 he published a list of vestigial organs. He writes, "comparative morphology points not only to the essentially similar plan of organization of the bodies of all vertebrates, ... but also to the occurrence in them of certain organs, or parts of organs, now known as 'vestigial.' “By such organs are meant those which were formerly of greater physiological significance than at present.”
He picked up on Darwin’s concept of “rudimentary” organs such as listed in the "The Descent of Man": the muscles of the ear, wisdom teeth, the appendix, the coccyx (tail bone), body hair, and the semilunar fold in the corner of the eye. This list was used as an argument for evolution as they were seen as evolutionary leftovers, of little use to the current organism. The list, however, contains structures which today are known to be essential, and thus represents a historical record of the physiologic understanding of the day. Creationists, on the other hand, have used the discredited examples of the list as an argument against evolution. One of the reasons being that there is no "scientific" proof of the uselessness of something - if you come across something that you don't know whats its use is, then that could simply imply your own ignorance of its utility. An example would be a "shoe horn" - a simple piece of metal that looks like a spoon with the part that should hold food inside out. This on casual glance would appear to be useless as a spoon, if that's what it was assumed to be.
Some biologists have asserted that it is impossible to identify useless organs.
Its shortcomings have been almost universally pointed out by modern authors, but the idea still has a prominent place in biological mythology.
—P. Erlich and *R. Holm, The Process of Evolution (1963), p. 66.
Since it is not possible to unambiguously identify useless structures, and since the structure of the argument used is not scientifically valid, I conclude that `vestigial organs' provide no special evidence for the theory of evolution.
—S. Scadding, Do `Vestigial Organs' Provide Evidence for Evolution?" Evolutionary Theory (1981), pp. 173-176.
Many vestigial organs have now been discovered by medical science to have fundamental uses without which selection value is reduced. Many others simply act as "backup" being able to mimic or complement the function of other organs.
Although originally publishing 86, later interpretations enlarged Wiedersheim's list to 180 vestiges. Thus the zoologist Newman stated in the Scopes Monkey Trial: "There are, according to Wiedersheim, no less than 180 vestigial structures in the human body, sufficient to make of a man a veritable walking museum of antiquities."
It is important to note that a vestige is not necessarily a completely useless organ. Although defined as "useless" in popular media, a vestige as defined in evolutionary biology may still have some use, but the use has since diminished. This definition is consistent with Wiedersheim, who said that vestigial organs are "wholly or in part functionless" (Wiedersheim 1893, p. 200) and have "lost their original physiological significance" (p. 205).
[edit] Structures included in Wiedersheim’s list of 86 vestigial organs
- Adenoids
- Appendix, now speculated to assist with the body's immune system, also providing a storage site for beneficial bacteria during natural bowel cleansing. Its most important role is secreting an oil for lubrication of the large intestine, being as it is situated just before the only part of the bowel that goes uphill. Some people that have had their appendix removed develop some form of bowel cancer or liver cancer years later. "There is no longer any justification for regarding the vermiform appendix as a vestigial structure."—*William Straus, Quarterly Review of Biology (1947), p. 149.
- Body hair
- Coccyx
- Ear muscles for wiggling
- Lachrymal glands
- Nictitating membrane of eye
- Nipples on males.
- Nodes on ears, "Darwin's points"
- Parathyroid
- Pineal gland
- Pituitary gland
- Plantaris muscle
- Thymus
- Toes bones III, IV, V
- Tonsils
- Valves in veins
- Wisdom teeth
[edit] See also
[edit] References
- Wiedersheim, R. (1893) The Structure of Man: An Index to His Past History. Second Edition. Translated by H. and M. Bernard. London: Macmillan and Co. 1895.
- Goerttler K. Wegbereiter unserer Naturwissenschaftlich-Medizinischen Moderne: 219 Biographien zur Portrait-Sammlung des Anatomen Robert Wiedersheim (1848-1923)Academia-Press, Germany, 2003. ISBN 3-00-011942-6 / 3000119426
