Atoms did not "exist" in the sense that they had conscious experience of "life", they just were: solitary units. The excitation of these building block atoms, caused by exposure to an energy source (that of the sun or perhaps even lightening) presumably lead to the atoms adopting their simplest collective form: that of invariant patterns or stable structures. Something is considered stable if it is significantly permanent or common enough to deserve a name. It is assumed that these stable structures took the form of chains and that single free floating building block atoms had a natural affinity towards building block atoms of the same kind. Thus attraction and coupling of "same-kind" building blocks lead to the development of larger, more complex stable structures.

Perhaps due to chance (or due to the larger molecules becoming unstable), divisions began to occur. Splits occurred in such a way that one molecule became two individual chains: each chain being an exact copy of the other. In this way, chains become replicators. Replication occurred and continued to occur because it was stable. The stable survived and replicated while the unstable failed to continue to exist because their instability prevented them from replicating. Thus, Dawkins speculated that the earliest form of natural selection was simply a selection of stable forms and the rejection of unstable ones.

The survival of molecules depended on their successfulness at duplicating themselves. Molecules that faithfully produced replicas of themselves ensured the survival of that molecule "type" into the next generation. Occasionally, rare copying errors which were stable occurred that increased the diversity within the "replicator pool".

Dawkins views stability, and hence success, as having 3 constituents:

  1. Longevity: molecules that survived long enough to reproduce must be successful
  2. Fecundity: molecules that replicate rapidly tend to become more numerous and hence have a larger proportion of replicas entering the next generation
  3. Copying Fidelity: molecules that copy themselves accurately guarantee their own molecular structure’s survival into the next generation

The success of the replicators lead to increasing demand on the smaller solitary building blocks, which in turn led to competition. Replicators were selected simply because they were more successful and hence survived to replicate again. This struggle for existence among the replicator varieties led to a process of improvement that was cumulative. Ways of increasing stability and decreasing rivals’ stability became more elaborate and efficient. Some may have discovered how to break up molecules of rival varieties chemically, others perhaps learnt how to protect themselves, either chemically or by building a physical wall of protein around themselves. These were the first survival machines, which also became more and more developed and competition became stiffer. Eventually these survival machines evolved into the "survival machines" present today, namely ourselves and all other animals, plants, bacteria and viruses, and the replicators now go by the name of "genes".

Immortal coils

"Different sorts of survival machine appear very varied on the outside and in their internal organs… Yet in their fundamental chemistry they are rather uniform, and, in particular, the replicators that they bear, the genes, are basically the same kind of molecules in all of us – from bacteria to elephants. We are all survival machines for the same kind of replicator – molecules called DNA – but there are many different ways of making a living in the world, and the replicators have built a vast range of machines to exploit them."

In order to summarise this chapter, it is best to divide it into two different sections, according to its title. The first part of the chapter is concerned with the "coils" of DNA, their structure, and their functions. The second part of the chapter is concerned with the "immortality" of these coils and how this immortality labels them as the obvious unit of natural selection. I will discuss these two topics separately.

  By PanEris using Melati.

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