The Miller-Urey Experiment

In 1953, in the University of Chicago, two bright young men performed an experiment that would later become the landmark moment in the history of experimental abiogenesis, aka, "life in a test tube". Stanley Miller and Harold Urey created, from the hypothetical primordial soup, actual amino acids, the building blocks of life. This was hailed as a huge step forward for the Theory of Evolution, and is still printed in many science textbooks (Apex, Technical Lab Systems, etc.) as the experiment that proved life could form on early earth. But is this experiment really so effective? And if it is, what does it mean for creationists? The Wikipedia page for this experiment (http://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment) was chock-full of jargon, pulling in words like "racemic mixture" and "optical isomers" with casual abandon. But dissecting this page and going further into the history of this setup tells a very different story.

First off, lets examine the gases found in the "primitive atmosphere" mentioned in the diagram. Miller and Urey sealed water, methane (CH₄), ammonia (NH₃) and hydrogen (H₂) into the sterilized circuit depicted above, then left the setup for regularly applying shocks to the mixture. Within a day, the mixture had turned pinkish in color, and after two weeks, analysis showed that around twenty different amino acids had formed in the solution. Ten percent of the carbon turned into organic material (not surprising, seeing as “An organic compound is any member of a large class of gaseous, liquid, or solid chemical compounds whose molecules contain carbon” [Wikipedia]), and eighteen percent of the methane turned into bio-molecules, which are “any molecule that is produced by a living organism”. Seeing as the body contains over fifty elements and a far greater number of molecules (simple and complex), that is not a very valid claim. But even now, we have yet to touch upon the greater problem faced by Miller and Urey – the actual proposed composition of the early earth atmosphere.

The rather fanciful sketch above provides a good example of what most people believe occurred during the early stages of the earth – volcanoes quietly smoked in the background, while oceans fostered the developing forms of life that abounded. Wikipedia says (in the three lines that are given regarding the early earth) that when the earth was first accreting itself, there was plenty of hydrogen, water vapor, methane and ammonia – perfect conditions for Miller and Urey. However, it goes on to say that “as the solar nebula dissipated” – meaning when the earth actually formed from the rocks and materials thrown out when the sun came together – “these gases would have escaped, blown off by the solar wind”. (http://en.wikipedia.org/wiki/Atmosphere_of_Earth#Earliest_atmosphere). When Miller and Urey found out about this, Miller tried to repeat the experiment using the new chemicals proffered (nitrogen, carbon-dioxide, inert gases, etc.). He got a colorless brew, with very few amino acids. (http://www.scientificamerican.com/article/primordial-soup-urey-miller-evolution-experiment-repeated/)

If you read the Scientific American article a bit further, you see a nice explanation to get around this – nitrites were formed concurrently with the former amino acids. Nitrites, as the article mentions, are extremely detrimental to amino acids, breaking them down rapidly. Of course, the scientist (named Bada) found a way around this – iron was capable of neutralizing the nitrites, and the element Fe had been found in various rockbeds said to be at the layer of primordial earth.  The only problem with thinking like this is that iron is a reducing agent, and is not like an anti-catalyst. An anti-catalyst can retard chemical reactions all day long, and remain unchanged for it, but a reducing agent (like the iron Bada proposed adding to the soup) loses an electron every time a reaction is halted (http://en.wikipedia.org/wiki/Reducing_agent). Considering the relatively small amount of iron present on the early earth’s surface (http://www.ux1.eiu.edu/~cfjps/1400/atmos_origin.html), it is highly unlikely there was enough iron to neutralize all the nitrites that were forming everywhere.

I realize that this is a massive topic, and that I have barely scratched the surface of this controversy. If any reader has any questions or contradicting information, please comment or message me.