The Origin and Evolution of Life on Earth

Search this Site

The Origin of Life

This web site explores origin of life theories starting with prebiotic evolution and the primordial soup, followed by  self replicating  RNA  molecules and the RNA world and finally the evolution of the first genes and proteins. Much of the material on this site is taken from two sources: The Mystery of Life's Origin: Reassessing Current Theories and The RNA World. The first is an excellent review of origin of life experiments and primordial evolution. These authors make several interesting observations and conclusions: 1) most origin experiments are so marred by investigator interference that they are meaningless 2) the laws of chemistry and physics preclude the existence of the primordial soup 3) energy sources do not overcome the laws of thermodynamics because they are more often that not destructive. The second resource explains many of the issues associated with RNA self replication and really calls into question whether or not the RNA world ever existed. 

This site will also make several novel contributions to the origins debate:

1) The first living organism can not be simple because it must know how to use energy to self replicate. In fact, energy sources will be destructive unless mechanisms are in place to couple replication to the energy source. This coupling mandates a complex system. Thus, simple self replicating proteins and RNA molecules cannot exist because they violate the most basic laws of physics. This explains why researchers have yet to find one.

2) A much more thorough  analysis of the information found in proteins and DNA leading to a better understanding of the challenges that the first living organism faced as it evolved into more complex life. Statistical models developed here will show that the evolution of new genes and proteins requires evolution to routinely overcome dismal odds. In fact, the odds for success are so low that even given a trillion year no progress is expected.  But the real challenge is still Life's origin. Life needs a way to couple energy sources to its replication. It also needs a way to use energy to synthesize the subunits it needs for replication. None of this is simple. It is very likely that the first living thing was a fully developed cell. It would be simple by today's standards but nonetheless it would contain proteins and DNA and RNA and lipids.This is what is required to ensure a robust self replicator that can undergo further evolution. In the end, this complexity is a form of useful information or knowledge. That is life knows how to and has systems in place to couple energy sources to its replication.

I have written a few computer programs to model evolution.  These programs illustrate how natural selection and chance work together to create new useful information (knowledge). The programs show that it is easy to create new knowledge (in a gene)  by rearranging existing knowledge (in other genes). Thus, evolution today works much better than it did when life first began. The programs show how difficukt it is to create useful information when starting from scratch (as would be the case for all origin of life theories).

When Stanley Miller synthesized amino acids in a spark chamber, I think that scientists everywhere thought that  the mystery of life's origin would soon be solved. But 60 years later it seems that science is further from an answer not closer. The origin of life on earth remains a mystery.

The RNA World and Self Replication

Without the knowledge  to couple an energy source to the process of replication,  RNA (or protein) self replication  just does not happen. Any  self replicating molecule (RNA or protein)   must know how to use energy sources to replicate. In other words, there is no such thing as a simple self replicating molecule. The above conceptual model does not work. The simplest living organisms are complex cells and have always been complex cells. We cannot invoke a simple self replicating system evolving under the direction of natural selection to explain life's origin because these simple systems do not exist. Read more about  the  RNA world  here. One could theorize that the first living thing was an RNA molecule (maybe bound to some proteins), and it might look like the picture below. The RNA/protein complex would have many active sites ( that couple the sun's energy) to drive the synthesize of all the subunits in the complex. It would also have to be able to unfold identical molecules and replicate them. Such a thing is allowed by the laws of physics but its complexity would rival that of a simple cell.

Does the Origin of Life Imply Design?

If you enjoy the web site please consider buying the book. Even if you just give it to your kid or a friend. Amazon determines search rankings based on sales. So your purchase helps others find it.

Click on the cover to read front and back cover.

The best book ever written on the origin of life (no not mine) is available free. Just click on its cover.