Origin of Life

Last year I blogged about Robert Shapiro’s excellent article in Scientific American that gave cogent critiques of many standard models of the chemical origin of life. Shapiro critiqued the view that a primordial soup existed on the early earth that ultimately gave birth to a self-replicating molecule, which eventually evolved into RNA and then DNA. After critiquing this standard model, Shapiro gave his alternative explanation, proposing that life evolved from metabolic pathways that naturally occurred on the early earth. As I wrote at that time, Shapiro “gives scant explanation for how these life-like metabolic networks can come into existence naturally, and he gives no details as to how these thermodynamic states produce real life–life as we know it today.” Now Read More ›

[Editor’s Note: This is slide 12 in a series of 14 slides available at JudgingPBS.com, a new website featuring “Darwin’s Failed Predictions,” a response to PBS-NOVA’s online materials for their “Judgment Day: Intelligent Design on Trial” documentary.] If, as Slide 11 suggests, human origins are a mystery to Darwinian scientists, the chemical origin of life presents a far greater challenge. As Gregg Easterbrook recently wrote in Wired Magazine, “What creates life out of the inanimate compounds that make up living things? No one knows. How were the first organisms assembled? Nature hasn’t given us the slightest hint. If anything, the mystery has deepened over time.”1 Origin of life theorists have struggled simply to account for the origin of pre-biological organic Read More ›

This post will provide a final discussion of an article in Scientific American entitled “A Simpler Origin for Life” by Robert Shapiro. Part I explained why the Miller-Urey experiment and the DNA-first hypothesis is deficient. In Part II, I explained Shapiro’s apt criticisms of the RNA-world hypothesis. Those who have abandoned the RNA-world hypothesis still seek a self-replicating molecule to qualify as the climax of chemical-origin of life scenarios–the “pre-RNA world.” However, Shapiro observes not only that “no trace of this hypothetical primal replicator and catalyst has been recognized so far in modern biology,” but also that “the spontaneous appearance of any such replicator without the assistance of a chemist faces implausibilities that dwarf those involved in the preparation of Read More ›

Writing in Scientific American Robert Shapiro recounts many criticisms of popular models for the chemical origin of life. Part I recounted why many origin of life theorists reject the possibility that DNA was the first genetic molecule. As noted, Shapiro even takes aim at those who suggest that the Miller-Urey experiment chemistry was important for forming prebiotic molecules on meteorites because studies of these meteorites show “a bias toward the formation of molecules made of fewer rather than greater numbers of carbon atoms, and thus shows no partiality in favor of creating the building blocks of our kind of life.” Due to these deficiencies, Shapiro then notes that increasing numbers of prebiotic chemists now turn to RNA as the first Read More ›

In an article titled “A Simpler Origin for Life” — a title which hides the implication of the article, Robert Shapiro, writing in Scientific American, highlights many problems with chemical origin of life scenarios. Shapiro quotes Richard Dawkins on his worship of the first self-replicating molecule and says “[a]t some point a particularly remarkable molecule was formed by accident. We will call it the Replicator.” (emphasis in original) That’s “Replicator” with a capital “R“. But, as Shapiro explains, the conventional explanation is not nearly so simple: Unfortunately, complications soon set in. DNA replication cannot proceed without the assistance of a number of proteins — members of a family of large molecules that are chemically very different from DNA. Proteins, like Read More ›