Posted September 13, 2005
On the website for Jonathan Wells's book Icons of Evolution, there's a page titled "Ten questions to ask your biology teacher about evolution."
All are about supposed flaws in the "Icons of Evolution" -- the Miller-Urey experiments, Darwin's Finches, Horse Evolution and more.
Here is Question #1:
ORIGIN OF LIFE. Why do textbooks claim that the 1953 Miller-Urey experiment shows how life's building blocks may have formed on the early Earth -- when conditions on the early Earth were probably nothing like those used in the experiment, and the origin of life remains a mystery?
This week, NASA's Astrobiology Institute and Washington University in St. Louis made an announcement that should, once again, sound the death-knell for this particular "Icon of Anti-Evolution."
Before discussing the new work, it's worthwhile to review a few points:
As Alan Gishlick points out in his article on the Miller-Urey experiment,
...Wells's claim that researchers are ignoring the new atmospheric data, and that experiments like the Miller--Urey experiment fail when the atmospheric composition reflects current theories, is simply false. The current literature shows that scientists working on the origin and early evolution of life are well aware of the current theories of the earth's early atmosphere and have found that the revisions have little effect on the results of various experiments in biochemical synthesis. Despite Wells's claims to the contrary, new experiments since the Miller--Urey ones have achieved similar results using various corrected atmospheric compositions ...Even if Wells had been correct about the Miller--Urey experiment, he does not explain that our theories about the origin of organic "building blocks" do not depend on that experiment alone.... In fact, what is most striking about Wells's extensive reference list is the literature that he has left out. Wells also fails to cite the scientific literature on other terrestrial conditions under which organic compounds could have formed....
There are other problems with Wells's argument -- Miller got a high yield of bio-molecules in just a week (think what he could have done with a few hundred million years at his disposal); perhaps life did not begin in the atmosphere, but in anoxic or reducing environments like undersea volcanic vents; and so on.
Miller's major breakthrough was that he showed amino acids could form outside of cells -- not by carefully synthesizing them, as some had done by then, but simply by mixing naturally-occurring gasses and adding some energy. Finally, the Miller-Urey experiment is more of an Icon of OOL (Origin Of Life) than of evolution per se.
So, what's the new work that adds another nail to this anti-evolution icon's coffin?
The September 7, 2005 announcement, titled "Calculations favor reducing atmosphere for early Earth," says
Was Miller-Urey experiment
Using primitive meteorites called chondrites as their models, earth and planetary scientists at Washington University in St. Louis have performed outgassing calculations and shown that the early Earth's atmosphere was a reducing one, chock full of methane, ammonia, hydrogen and water vapor.
In making this discovery Bruce Fegley, Ph.D., Washington University professor of earth and planetary sciences in Arts & Sciences, and Laura Schaefer, laboratory assistant, reinvigorate one of the most famous and controversial theories on the origins of life, the 1953 Miller-Urey experiment, which yielded organic compounds necessary to evolve organisms.... "Geologists dispute the Miller-Urey scenario, but what they seem to be forgetting is that when you assemble the Earth out of chondrites, you've got slightly different gases being evolved from heating up all these materials that have assembled to form the Earth. Our calculations provide a natural explanation for getting this reducing atmosphere," said Fegley.
Schaefer presented the findings at the annual meeting of the Division of Planetary Sciences of the American Astronomical Society, held Sept. 4-9 in Cambridge, England. The Miller-Urey experiment featured an apparatus into which was placed a reducing gas atmosphere thought to exist on the early Earth. The mix was heated up and given an electrical charge and simple organic molecules were formed. While the experiment has been debated from the start, no one had done calculations to predict the early Earth atmosphere.
"I think these computations hadn't been done before because they're very difficult; we use a special code" said Fegley, whose work with Schaefer on the outgassing of Io, Jupiter's largest moon and the most volcanic body in the solar system, served as inspiration for the present early Earth atmosphere work....
Another Icon of Anti-evolution down -- again. But never fear -- it'll be back. Like my dad always said,
Creationist arguments are like ducks in a shooting gallery. No matter how many times you shoot them down, they just pop right up again.
That reminds me, has this topic come up on the Thumb before? Of course!
Mr. Dave Thomas is a physicist and mathematician, employed at a small high-tech testing firm in Albuquerque, NM. He received bachelor degrees in mathematics and in physics, and a master of science in mathematics, from the New Mexico Institute of Mining and Technology, where he was awarded the Brown Medal and the Langmuir Award. Dave is president of the science group New Mexicans for Science and Reason (http://www.nmsr.org), and also is a Fellow of CSICOP (Committee for Scientific Investigation of Claims of the Paranormal), the publishers of Skeptical Inquirer. He can be contacted at nmsrdaveATswcp.com (please help fight SPAM -- replace AT with @)