More Common Myths About Evolution
Darwin’s Theory Seems to be a Cause of Misunderstanding in the U.S.
Mar 2, 2009
In 2009, the bicentennial of Darwin’s birth, a Gallup poll shows that only about 51% of Americans “believe” in evolution, placing the United States near the bottom of the nations polled. Inadequate science education may play a part in the confusion over evolution. However, some of the misunderstanding stems from attempts by creation/intelligent design proponents to muddy the waters and manufacture “debate” where none exists. A few more common myths include:
Evolution is “Controversial”
The theory of evolution is, among scientists, exactly as controversial as the “theory” of gravity or the “theory” that the Earth orbits the sun. No serious scientists working in relevant fields doubt that evolution happens, and that natural selection is the primary mechanism through which speciation takes place. Despite this consensus, evolution-deniers persist in arguing that evolution is a “discredited” science, publishing books which portray scientists scrambling desperately to save their dogmatic theory against the righteous onslaught of creationist truth.
But the “controversy” over evolution is entirely drummed up by those uncomfortable with its implications; it is a social and political controversy, not a scientific one. Legitimate scientists who doubt evolution are vanishingly few, and in any case are not usually trained in relevant fields. While there are still many questions to be answered in regards to evolution — rates of species change, the role of genetic drift — the scientific community is unified in its acceptance of the theory, having tested it against the evidence again and again and found it a solid, highly predictive tool for understanding the diversity of life.
“10% of a Wing”
Natural selection produces new species, but the process is almost unimaginably slow. Because of this, some argue that evolution would produce various “half-finished” creatures, possessing a useless 10% of a wing or 2% of an eye. This has been called the “incipient structure problem.” From our historical vantage point, knowing the outcome of various lineages, it is easy to look back at the fossil record and say the animal was “halfway between a reptile and a bird” or “halfway between a land mammal and a whale.” It is important to understand, though, that each creature at the time that it lived adapted to its unique conditions.
There is also the question of “exaptation,” in which a structure adapted for one purpose becomes useful for something else. There existed, for example, a group of feathered dinosaurs that could not fly, suggesting that feathers originally evolved for some use other than flying, and later were exapted for flight. In direct response to the incipient structure problem, then, we can say that any modification — two percent vision as opposed to one or none, or the ability to jump and glide as little as an extra inch or two — could have been all the edge a creature needed to escape predators and get a leg up on the competition.
“Irreducible Complexity”
Though the idea goes back to the early 20th century, the term “irreducible complexity” was coined by biochemist Michael Behe in his book Darwin’s Black Box. Behe argues that some structures in nature are too complicated to have arisen solely through the indifferent agency of natural selection. His popular examples include the human eye and the bacterial flagellum “motor,” both indeed amazing adaptations. Behe insists that these structures would not have worked if assembled piecemeal over long periods of time and therefore must have been constructed by a supernatural “intelligence.”
Natural selection, however, is quite capable of explaining the intricacies of life, without recourse to a divine interceder. The human eye, for example, is actually not optimally designed; outside images appear on the retina upside down and backwards, and the placement of the optic nerve causes a blind spot that our brains must compensate for. Additionally, antecedents to the “camera” eye of humans appear everywhere in nature, from the cluster of light sensitive proteins on the unicellular euglena to the superior camera eye of the octopus, so it is quite easy to see a pathway by which a complicated eye such as ours could have evolved. The same could be said of the bacterial flagellum, which, while certainly complex, is not nearly as machine-like as intelligent design advocates claim.
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