Below are some excerpts from Top Five Problems with Current Origin-of-Life Theories by Casey Luskin. In the article he explains that the chemical environment of the early earth was not conducive to the development of organic molecules nor was it conducive to forming long the polymers of organic molecules found in living cells. It is unlikely that a self-replicating molecule of RNA, a candidate for the first self-replicating molecule, could have arisen in that environment. It is also unlikely that the genetic code arose through the unguided action of natural laws because there is no way to explain how the system of producing proteins by decoding the DNA could arise from something simpler. For any of it to be useful you need the entire system. There is currently no valid scientific explanation for how life arose on earth.
In Casey Luskin's words, the problems are:
- No Viable Mechanism to Generate a Primordial Soup.
- Forming Polymers Requires Dehydration Synthesis
- RNA World Hypothesis Lacks Confirming Evidence
- Unguided Chemical Processes Cannot Explain the Origin of the Genetic Code.
- No Workable Model for the Origin of Life
Problem 1: No Viable Mechanism to Generate a Primordial Soup.This optimistic picture began to change in the late 1970s, when it became increasingly clear that the early atmosphere was probably volcanic in origin and composition, composed largely of carbon dioxide and nitrogen rather than the mixture of reducing gases assumed by the Miller-Urey model. Carbon dioxide does not support the rich array of synthetic pathways leading to possible monomers...3
Problem 2: Forming Polymers Requires Dehydration Synthesis
Chemically speaking, however, the last place you'd want to link amino acids into chains would be a vast water-based environment like the "primordial soup" or underwater near a hydrothermal vent. As the National Academy of Sciences acknowledges, "Two amino acids do not spontaneously join in water. Rather, the opposite reaction is thermodynamically favored."
Problem 3: RNA World Hypothesis Lacks Confirming Evidence
For one, the first RNA molecules would have to arise by unguided, non-biological chemical processes. But RNA is not known to assemble without the help of a skilled laboratory chemist intelligently guiding the process. New York University chemist Robert Shapiro critiqued the efforts of those who tried to make RNA in the lab, stating: "The flaw is in the logic -- that this experimental control by researchers in a modern laboratory could have been available on the early Earth."13
RNA world advocates suggest that if the first self-replicating life was based upon RNA, it would have required a molecule between 200 and 300 nucleotides in length.15 However, there are no known chemical or physical laws that dictate the order of those nucleotides.16 To explain the ordering of nucleotides in the first self-replicating RNA molecule, materialists must rely on sheer chance. But the odds of specifying, say, 250 nucleotides in an RNA molecule by chance is about 1 in 10150 -- below the "universal probability bound," a term characterizing events whose occurrence is at least remotely possible within the history of the universe.1
Problem 4: Unguided Chemical Processes Cannot Explain the Origin of the Genetic Code.The nucleotide sequence is also meaningless without a conceptual translative scheme and physical "hardware" capabilities. Ribosomes, tRNAs, aminoacyl tRNA synthetases, and amino acids are all hardware components of the Shannon message "receiver." But the instructions for this machinery is itself coded in DNA and executed by protein "workers" produced by that machinery. Without the machinery and protein workers, the message cannot be received and understood. And without genetic instruction, the machinery cannot be assembled.20
Problem 5: No Workable Model for the Origin of Life
Massimo Pigliucci states: "[I]t has to be true that we really don't have a clue how life originated on Earth by natural means."22 Or as science writer Gregg Easterbrook wrote in Wired, "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."23
Likewise, the aforementioned article in Cell Biology International concludes: "New approaches to investigating the origin of the genetic code are required. The constraints of historical science are such that the origin of life may never be understood."24 That is, they may never be understood unless scientists are willing to consider goal-directed scientific explanations like intelligent design.
Copyright © 2013 by ncu9nc All rights reserved. Texts quoted from other sources are Copyright © by their owners.