Natural Selection and Evolution

Natural Selection and Evolution

Many scientists believe that the vast expanse of the universe and its extreme age offset the poor odds associated with the origin of life, but they never present calculations to support this conclusion. Instead, they assume that it must be true because life exists, and they rely on the naturalistic axiom to support their position. By definition this approach is science. Nevertheless, why not do the calculation?

        For chemical evolution, both the vastness and age of the universe help. For biological evolution only time helps because if life exists on other planets it is extraordinarily rare. Biological evolution also benefits from large populations. This chapter will show that when large populations are given several billion years to evolve, the knowledge that they create is insufficient to explain the origin of many proteins.

        This chapter only considers two cases: 1) The evolution of the very first genes and proteins. These arose shortly after self replication evolved. 2) The evolution of molecules capable of self replication. Thus, the scope of this chapter is limited to the earliest stages of evolution.

       Natural selection is often seen as the driving force behind evolution. This chapter will show that rather than drive evolution, natural selection often works against it. By preserving favorable traits, natural selection allows nature less freedom to explore new possibilities. The net result is fewer tries. So if the probability of a particular evolutionary transition is low because the step in molecular knowledge is large, then  the primary influence of   natural selection is to ensure that the transition does not happen.

       This observation does not mean that natural selection does not work like Darwin theorized. If chance creates a new more fit trait natural selection will preserve it just like Darwin proposed.  The net result  is twofold. Natural selection is very effective a driving small evolutionary changes that require small steps in molecular knowledge, but it works against large evolutionary changes that require large steps in molecular knowledge.

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