Natural Selection and Evolution

Self Replicating without Natural Selection

Assume that the first self- replicating system is able to reproduce at the same rate as bacteria. Further assume that this system is a single RNA molecule. Can such a system evolve? We will consider a system   without natural selection first, and we will find that the odds for evolution when the steps in molecular knowledge are large are more likely in systems without   natural selection.

   This system certainly gets plenty of tries ~ 10³⁰ per year. How much information can it create given a billion years if each replication event counts as one try? In one billion years, this self-replicator will accumulate approximately 10³⁹ tries. Such a system has a 63% chance of generating 130 bits of molecular knowledge. Figure 15.6 illustrates how self replication and the number of tries that it generates help the scientist to climb a wall of knowledge. Perhaps more impressive, self-replicators (like bacteria) can create 100 bits of knowledge in a single year! This looks encouraging for evolution.

Figure 15.6: Self Replication Helps Increase the Number of Tries

The Trees Help, but . . .

Self replicators cannot accumulate ~10³⁰ tries per year unless they can replicate this many times per year. This replication will undoubtable require an almost unlimited supply of adenine, cytosine, ribose, uracil, and thymine. Given that these are so difficult to synthesis in the lab under plausible pre-biotic conditions, in order for the self replicators to accumulate ~10³⁰ tries per year, they must be able to at least synthesize adenine and ATP. Thus, there is no clear path for evolution.

       Chapter 14 calculates the molecular knowledge of the enzymes responsible for adenine synthesis and ATP at 15,364 bits in the soup and 2,771 bits with the genetic code. These enzymes are required by the self replicators to make adenine so they can self-replicate. Nevertheless, assume (as all evolutionists have) that perpetual motion machines are acceptable when they are needed to explain the origin of life. With this assumption, the self replicators still get ~10³⁰ tries per year, and evolution still fails (see figure 15.7).

Figure 15.7 - Time Does Not Help When The Odds Are This Poor

Figure 15.7 - Time Does Not Help When The Odds Are This Poor This entire discussion boils down to the chicken or the egg paradox which came first. Evolution needs large populations that replicate quickly to create knowledge. But self-replicators cannot replicate quickly unless they can synthesize adenine, ATP and host of other chemicals. This first step is so large that even with the perpetual motion assumption evolution fails, and it only gets worse from here.

The next page will show that natural selection is not a solution to this problem. In fact, natural selection is just an aggravating factor.

Next: Natural Selection Limits the Number of Tries

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