After all that, perhaps now is a good time to continue the thread topic. Cofty, a few questions for you. Which one of the abiogenesis theories do you support? Quite a few doing the rounds. What, in your opinion, would have been first, the cell or the gene? If it was the gene, DNA or RNA? High levels of ultaviolet light would have affected the gene adversely, so perhaps first the protective layer of a cell would be necessary. In a deep sea environment the ultraviolet threat would be cancelled out.
The general one is the “RNA world” theory, which posits that RNA – the molecule that today plays roles in coding, regulating, and expressing genes – elevated itself from the primordial soup of amino acids and cosmic chemicals to give rise first to short proteins called peptides and then to single-celled organisms.
However, for the hypothesis to be correct, ancient
RNA catalysts would have had to copy multiple sets of RNA blueprints nearly as
accurately as do modern-day enzymes. That’s a hard sell; scientists calculate
that it would take much longer than the age of the universe for randomly
generated RNA molecules to evolve sufficiently to achieve the modern level of
sophistication. Given Earth’s age of 4.5 billion years, living systems run
entirely by RNA could not have reproduced and evolved either fast or accurately
enough to give rise to the vast biological complexity on Earth today.