Thursday, January 7th, 2010

A house from the days in which Jesus walked the streets of Nazareth has been uncovered.  Amazing!

As a result of the failure of the chance hypothesis to explain the origin of life, Dean Kenyon and Gary Steinman proposed a novel solution: life’s origin is due to physical necessity, not chance (Biochemical Predestination, 1969).  Like many others in their day, Kenyon and Steinman were proponents of the protein-first model, maintaining that the first life was based on proteins rather than DNA (DNA came later).  They got around the utterly implausible odds of forming proteins by chance by just denying that chance was involved at all.  They suggested that law-like processes direct the self-organization of chemicals, making the origin of life inevitable, not some lucky happenstance.  Just like electrostatic forces draw sodium and chloride together in ordered patterns to form crystals, some (yet-to-be-discovered) natural law organized biochemicals to form the biological information that makes life possible. 

As evidence for their view that proteins could self-organize to form the basis of life, they pointed to the fact that amino acids bond with certain other amino acids better than others, making certain sequences more likely than others.  This explained how the biological information necessary for life could arise without DNA, RNA, and the transcription-translation process.[1]

Eventually, however, Kenyon came to question his model.  He recognized that even if it could explain the origin of biological information, he still needed to explain the origin of DNA as well as how protein synthesis transformed itself from a self-organizing and self-originating process to one that depended entirely on DNA transcription and translation.  He dismissed the possibility that proteins constructed DNA because the information flow in modern cells is unidirectional, and it’s in the complete opposite direction: information flows from DNA to proteins, not vice-versa.  Because DNA wholly determines the amino acid sequencing of proteins, and because there is no evidence suggesting or reason to think this order was ever different in the past he eventually abandoned the protein-first model.  DNA must have come first.  But based on his knowledge of its chemical properties, he doubted that DNA possessed the same sort of self-organizational properties he thought were present in amino acids.  He was forced by the evidence to abandon his proposal that life originated by necessity.