Realistically Speaking

Harvard Medical School»
HOME: MEDICINE+HEALTH
Did life originally spring from clay?Researchers find a role for clay in formation of the first cells. November 6, 2003
While the research is a far cry from proving that humans sprang from clay, as some creation myths assert, it does provide a possible mechanism for explaining how life initially arose from nonliving molecules. Researchers at the Howard Hughes Medical Institute and Massachusetts General Hospital showed that the presence of clay aids naturally occurring reactions that result in the formation of fatty sacks called vesicles, similar to what scientists expect the first living cells to have looked like. Further, the clay helps RNA form. The RNA can stick to the clay and move with it into the vesicles. This provides a method for RNA's critical genetic information to move inside a primitive cell. Harvard Medical School Professor of Genetics Jack Szostak said he and colleagues Martin Hanczyc and Shelly Fujikawa aren't suggesting they've hit on the exact method by which life initially arose. Still, he said, there are exciting parallels. "It's exciting because we know that a particular clay mineral helps with the assembly of RNA," Szostak said. "There certainly would have been lots of environments on early Earth with clay minerals. It's something that forms relatively easily as rocks weather."
Harvard University Gazette

A model for the origin of life based on clay was forwarded by Dr A. Graham Cairns-Smith of the University of Glasgow in 1985 and adopted as a plausible illustration by several other scientists, including Richard Dawkins. Clay theory postulates that complex organic molecules arose gradually on a pre-existing, non-organic replication platform — silicate crystals in solution. Complexity in companion molecules developed as a function of selection pressures on types of clay crystal is then exapted to serve the replication of organic molecules independently of their silicate "launch stage"

The following is a quoted passage written by Michael Talbot, New York City, February 1984, as quoted from "Windows of Light", by Randall & Vicki Baer:

"Crystals are dramatic examples of the capacity of matter to self-organize. As we saw in the incident related by Holden and Sanger, they can also acquire and retain information-- for example, their geometric structure-- and reproduce copies of themselves containing the same information. Given that they perform all these functions while remaining far more stable and durable than DNA, Cairns-Smith believes that crystals make very likely candidates as the most ancient progenitors of life. However, to more fully establish his case, Cairns-Smith knew that he had to find a crystal that possessed one further quality, the ability to use the information it possesses to interact with its environment..."

"...Clays not only have the ability to grow and adsorb other molecules, but they can then incorporate the information from those molecules and use it to alter and change themselves. Clays were almost most certainly among the most abundant substances on the early Earth. Even while the Earth was still too hot to support life as we know it, cooling rains poured down upon the mountains and the rocks, slowly pulverizing them into vast percolating beds of clay. Cairns-Smith believes that it was clay itself that formed the first link between life and nonlife. In his book "The Life Puzzle", he sketches out a possible evolutionary description fo three different species of clay he calls Sloppy, Sticky, and Lumpy..."

"Lumpy solved this problem by accidentally picking up just enough organic molecules to make it both a little sloppy and a little sticky. Having the thick, coagulated consistency of modern clays, Lumpy was able to grow rapidly, survive storms, and even spread, sending broken lumps of itself downstream to grow into new claybeds. In this way Lumpy not only interacted in a complex manner with its environment but also survived selective pressures. Add just one more trait to Lumpy-- the ability of crystals to apparently duplicate and pass on innovation-- as demonstrated by Holden and Sanger's crystals of ethylene diamine tartrate-- and you have everything necessary for the acquisition and inheritance of new characteristics, a quality hitherto believed confined to the realm of biological life..."

Cairns-Smith believes that it was inevitable that the clay would ultimately have assumed a secondary role, providing little more than a protective clamp, until at last, life broke free and started to form its own protective cell walls..."

Scientists are learning that what is required for life is much greater than what is possible by natural process. The huge difference has motivated scientists to creatively construct new theories for reducing requirements and enhancing possibilities, but none of these ideas has progressed from speculation to plausibility.

For example, in an effort to avoid a "chicken and egg" problem — in modern cells, DNA is required for protein synthesis, but protein is required for DNA synthesis — scientists have proposed that RNA (which combines the replicating ability of DNA and the catalytic activity of proteins) was the key life-producing molecule in the earliest cells. But this "RNA World" theory now seems implausible due to the apparent impossibility of pre-biological RNA synthesis, and because the catalytic activities of RNA have not matched initial optimistic hopes. In response, scientists are now proposing "pre-RNA World" theories with key functional roles played by other molecules, and with metabolic energy sources that would be easier to use.

Michael Behe illustrates the principle of irreducible complexity with a mousetrap that has five interacting parts: a base, hammer, spring, catch, and holding bar. Each part is necessary, and there is no function unless all parts are present. A trap with only four parts has no practical function. It doesn't just catch mice poorly, it doesn't catch them at all.
What are the evolutionary implications? Behe says, "An irreducibly complex system cannot be produced directly... by slight, successive modifications of a precursor system, because any precursor to an irreducibly complex system that is missing a part is by definition nonfunctional. An irreducibly complex biological system, if there is such a thing, would be a powerful challenge to Darwinian evolution." (DBB, page 39)
For a nonliving system, the implications are even more challenging, because natural selection — which is the main mechanism of Darwinian evolution — cannot exist until a system can reproduce. For the origin of life, we can think about the minimal complexity that would be required for reproduction and other basic life-functions. Most scientists think this would require hundreds of biomolecular parts, not just the five parts in a simple mousetrap.

The Szostak team has also built on the work of other scientists, who have shown that the same clay can help the formation of RNA, thought to be a precursor to the DNA that now serves as life's instruction book. Szostak showed that when fatty acids and RNA were mixed with the clay, these balloons formed with RNA trapped inside. A process like this, Szostak said, may have led to the first cell.

Scientists from California claim they support the emerging theory that life on Earth began in clay rather than the sea.
In their analysis of common ceramic clay, the scientists said they found evidence that "mistakes" made normally and repeatedly in the formation of clay crystals presumably create the condition by which the material traps energy and holds it for perhaps thousands of years.
Such defect in the clay microstructure could also be sites for storing information necessary to direct the chemical reactions and organize the eventual proto-organisms.It would seem that an accumulation of chemical mistakes led to life on Earth.

Comment:
In the scientific world, a mistake is often ued to explain unnatural or unexplainable behaviour. Scientists can only explain what occurs according to the laws of nature, which doesn't allow for any deviation. Scientists who believe in abiogenesis use several conjectures for explaining how life arose from non life. Evolution can explain survival of the fittest, but not how life started. Anything that doesn't follow the natural order of things,according to how science explains order, is considered a mistake. Many Scientists who are also Christians sometimes explain those "mistakes" as the work of the Creator. On the other hand some scientists believe that chance could have created life from non living matter, while refusing to believe that God could have created life from non living matter. It's easier for some to believe we are a mistake of nature than to believe we are a well thought out design.