In the case that polypeptides (polymers of proteins), nucleic acids (RNA), and polysaccharides (polymers of glucose or other sugars) are added to the solution, they become enclosed within the lipid bilayer and a coacervate, is formed.

Microspheres, liposomes and coarcervates are collectively called protobionts (aggregates of abiotically produced molecules).

Protobionts resemble cells in that they contain a protected by a lipid bilayer inner environment, and perform chemical reactions. They undergo osmotic swelling or shrinking when placed in different salt concentrations, they can store energy in the form of membrane potential, a voltage across the surface, which can be discharged in nervelike fashion (such excitability is characteristic of all life). Two main things are lacking at this point: enzymes (to make unfavorable chemical reactions such as metabolism possible) and hereditary material. Protobionts can reproduce to a certain extent: when they grow too large they split in half. That, however, dilutes the contents of the cell, and there is no way of perpetuating a certain successfull for survival combination of molecular aggregates.

    The RNA world

As noted in the first paragraph of this section, RNA chains form spontaneously in solutions mimicking the conditions on the primitive Earth. What is really the next turning point in the story of "life" is the observation that RNA can be self-replicating. In today's experiments, RNA sequences of about 5 to 10 nucleotides are copied from the original strand. If zinc is added as a catalyst, sequences up to 40 nucleotides long are copied with less than 1% error. The theory holds that RNA was capable of replicating with the same, or better success on the primeval Earth. Another very important discovery of the last years was that RNA possesses catalytic activity. Modern cells use RNA catalysts called "ribozymes", a fact that disproved the long-held view that only proteins (enzymes) serve as biological catalysts. The fact that RNA is autocatalytic strengthens the theory that RNA molecules were fully capable of self-replication (RNA autocatalyzes its replication)!
Thus, we have replicating autocatalytic RNA molecules and they were subjected to natural selection the same way that every population of future species would be. Unlike double-stranded DNA, which takes the form of a uniform helix, the single stranded RNA assumes a variety of 3D shapes determined by the nucleotide sequence: each sequence folds in a unique conformation and in this way, it has a variable chance of survival in the changing conditions. Also, the RNA molecule having the greatest autocatalytic activity will leave more copies of itself. Meanwhile, occasionally a mutation (a copying error) occurs, and that results in a molecule that folds into a shape even more stable or adept at self-replication than the ancestral sequence.

The next turning point in the origin of life would come when RNA would start serving as the template which would direct protein syntesis, a function that today is performed by DNA, and THE function for which nucleic acids are known for (besides the newly discovered catalytic function of RNA). It is not too clear how that occured, but it is thought that "molecular cooperation" was involved:
RNA molecules probably served as simple templates holding a few amino acids together long enough for them to be linked. If RNA happened to synthesize a short amino acid chain (polypeptide/protein) that in turn behaved as an enzyme helping the RNA molecule to replicate, then that would be the earliest case of "molecular cooperation" and it would be of huge importance to the future of life.
This step could have been taken even before RNA and polypeptides became packaged within membranes. The protection of the lipid bilayer was soon needed though, because it was the only way of taking advantage of the situation of "molecular cooperation": if an RNA molecule ordered amino acids into a primitive enzyme that extracted energy from an organic fuel and made that energy available for other reactions within the protobiont, particularly replication of RNA, natural selection would favor keeping all components close-by, because the energy would otherwise be lost to the surroundings.

  Life is ready to evolve

We have followed a scenario that brings us to a structure with the fundamental properties of today's cells. It is capable of accumulating monomers from its surroundings that are made into polymers thanks to enzymes that are programmed by genes. This protobiont grows and splits, distributing copies of its genes to offspring. Even if only one such protobiont arose initially by the abiotic processes described so far, its descendants would vary because of mutations (errors in the copying of RNA). Therefore, natural selection (Darwinian evolution) would be possible in its true sense: varying individuals would have differential reproductive success. In this way many refinements to primitive metabolism and inheritance could be made. One such change led to DNA becoming the hereditary material. Initially, RNA could have provided the template on which DNA nucleotides were assembled. Once DNA appeared it took over its present role from RNA because of its more stable backbone structure and the fact that it spontaneously forms a compact double-stranded helix.

  Before concluding this topic we should mention the theory of panspermia, which holds that the hundreds of thousands of meteorites and comets hitting the early Earth brought with them organic monomers formed by abiotic reactions in outer space. Extraterrestrial organic compounds, including amino acids have been found in modern meteorites and in 1994, scientists found evidence for the amino acid glycine in the spectrum of light emitted from a distant star-forming region. Nevertheless, this has not been a definite discovery.

    What is the "Selfish Gene" theory?

The following is all my interpretation and it might not represent the exact views on these subjects.

In short, the "Selfish Gene" theory says that genes (the nucleic acids RNA, DNA) are using "living things" to propagate. It turns the percepted view of "life" "using" DNA/RNA for its purpose around, and states that genes are using "life" for protection and survival.
Each and every living thing on Earth, from bacteria to humans exists with the utmost mission to reproduce. Its actions throughout its existance are guided mainly towards this goal. If it is achieved, after the organism's death the only thing that survives in time are the genes. The organisms are transient compared to the genes, which maintain a relatively unchanged state.

Isn't life a method of genes to protect, reproduce and spread themselves?
Isn't evolution about DNA finding more and better ways to do those 3 things?

Where is the support for the "Selfish Gene" theory?

As we will see, support might not be too hard to find. That is not to say that there is a way to prove this theory. It is rather a speculation than a theory, but one that deserves our attention.

Let's start to look for evidence in the dawn of life, in the events discussed above.
It serves well to ask to question: What is life? There is NO definite answer to that question. Science has not drawn a line between living and non-living, the classic example being the virus. Nevertheless, there are certain features that every candidate for the "alive" title needs to have. One of them is the ability to reproduce.
We are not talking, however, of the primitive protobionts that could grow up to a certain size and then split. Without hereditary material their contents is diluted and they are like the drop of water that splits in two as it grows when its surface tension breaks. That is NOT life. Life is defined as having the ability to make a progeny almost identical to the parent, in asexual reproduction, and sharing to a certain degree attributes from both parents in sexual reproduction. Obviously asexual reproduction preceded sexual reproduction with billions of years. How was it started? Where and how did this crucial property of life FIRST appear?
In RNA. As stated above, RNA was the first organic compound capable of self-replication. I believe that to be critical to further discussions since this is one of life's most important properties. Replication, or reproduction in the sense of life were first inherent only to RNA. Consider this statement given as an alternative hypothesis to the evolution of life in MCAT Biology, 2000 (see reference above): "Life began with self-replicating RNA floating free in the ocean. As it grew more complex, this early genome would require protection". We can consider, therefore, the primitive protobiont and the early RNA as two separate entities, until the moment when RNA incorporated itself within the lipid bilayer for its protection. Of course, here we can bring up the opposite theory: that the protobiont used the RNA for its own purposes as well. The truth however is that ONLY RNA had the most important attribute of life: replication. The protobiont exhibited chemical similarity to life, but these are not even close to being primary in what characterizes life. It does indeed seem that RNA utilized the primitive protobiont for its own purpose of replication. Moreover, replication was the inherent property of RNA before incorporation in protobionts, while growing and splitting (protobionts) seems more like a physical consequence rather than something else. Nevetheless after the incorporation, the new entity, protobiont with RNA, begins performing reproduction the way RNA dictates in that an almost exact copy of the strand is produced along with the same level of defense (the protobiont, or today's cell). And indeed, we can look at the problem as if nothing has changed since that ancient time. RNA ensures that its new copy is protected the same way as its parent, a result from the fact that RNA and later DNA have come to hold the information from which their protective environment is constructed.
Afterall, RNA-directed protein synthesis originated as RNA synthesized a polypeptide that behaved as an enzyme helping the RNA molecule to replicate (see above)!

Another important moment from the early Earth is the fact that RNA was one of the few (some amino acids have shown weak enzymatic properties) compounds capable of catalyzing unfavorable reactions. That marked the first organic compound to be able to facilitate biological reactions (clay, iron pyrite are inorganic catalysts). Note that it first catalyzed not any biological reactions, but its self-replication.

Why was DNA preceded by RNA? As mentioned above, unlike DNA, each RNA sequence folds in a unique conformation and in this way, it has a variable chance of survival in the changing conditions. That was necessary to ensure early survival by natural selection, because the more stable and more capable of replication and catalyzation strands would survive longer before eventually finding protection in the form of the protobiont (cell). Once settled in that environment, RNA as a repository of genetic information, could be replaced by the much more stable double-stranded DNA.

The theory of the "selfish gene" can be made consistent with "natural selection". We can simply switch the roles of "species having different reproductive success due to different gene order" to "genes ensuring their long-term survival via maintaining a pool of different sequences that code for their hosts". Thus, if a gene was replicated exactly the same way every time (no mutations-no natural selection), its host would be vulnerable to extinction at a change of environmental conditions. By ensuring code errors at replication (mutations), the genes are diversifying their hosts so that at a change of environment, some would be more adaptive than others and survive the stress. Indeed that's what the mainstream natural selection theory holds - over time mutations give rise to individuals that might be more resistant to some factor (climate change, disease). Thus, if the factor begins to play a role in the population the individuals that have become more tolerant of it will survive in the new conditions, and maybe give rise to a new species due to genetic drift (small sample of a population is not likely to be gentically representative of the original population). However -- what survives is not the old population, which goes down in history, but its genes (which of course are modified to include the change in towards the new factor; nevertheless, this is an insignificant change. As it is known mice and human DNA are nearly identical...).

Some possible implications

At the end of all the questions without answers there is one more left to ask. It is bigger than all the rest that we have seen so far, because it deals with the two fundamental domains of creation -- the living and non-living.
We are talking about DNA (which codes for what we call "life") and the incomparably more immense realm of physical matter that obeys today's physics laws. These two coexisting entities can clearly be separated on the basis of living and non-living.

There is, however, one line among which there is a striking similarity among the two and it deals with the level of understanding that contemporary science has of both DNA and the physical universe.