How did life actually originate? Where did the “stuff” come from on which natural selection could begin its work? Prebiological evolution is the subject of chapter 8. Evolution is the study of how life changes after it already exists and natural selection can only begin its work when it has something living to work on. The problem faced in this chapter is discovering how life began in the first place. What were the necessary chemical compounds that made life possible? What external force (perhaps electricity) combined with those compounds to produce self-sustaining life? A few theories have been proposed.
One theory is that Earth’s early atmosphere was conducive to the development of essential amino acids thought to be the precursors for life. Experiments were conducted hoping to replicate this atmosphere, in which a spark was sent through a mixture of gases that led to the production of two amino acids. Related to this theory is the contention that these early chemical compounds were produced to such an extent that it resulted in the “pre-biotic” soup from which life emerged. Geochemists have been quick to oppose this theory claiming that the “soup” could never have existed and therefore cannot be used as the model for the origins of life. The experiments themselves have also continually failed in producing “living organisms” that could themselves form amino acids and reproduce. The formation of these chemical compounds in an early earth atmosphere, whether a valid theory or not, according to Johnson, amounts to a level of chance that is another way of saying “miracle”.
Another theory proposed is the idea that an RNA molecule was developed that carried with it the necessary information for protein synthesis and reproduction. However, various scientists claim that RNA would not have been produced in significant enough quantities to account for life as we know it and RNA must have developed from some earlier “genetic system that no longer exists.”
Lastly, molecular biologist Francis Crick, half of the team that discovered the DNA molecule, proposed a wild solution to the origin of life on the planet. Although this solution was delivered in the face of great uncertainty over life’s origins and likely was never intended as concrete scientific model, he proposed that the development of life from complex molecules may have been a rare event in the universe but could have been used by highly advanced civilizations on distant planets in a process he called “directed panspermia”. Under this model an alien civilization could have spread molecular life to other planets using some form of space travel. He was ridiculed by hardcore evolutionists for this proposition for it amounts to nothing less than some form of intelligent design and it does not escape the problem of answering the initial question in the first place. Where did life itself originate? Crick’s speculation only moved the target of examination from Earth to another planet and demonstrates the length to which some scientists will go in speculating about the origins of life when clear evidence for its sudden appearance on the level of miracle is indeed plausible.
