While the scientific community, and most of the intelligent world, has widely accepted that the theory of natural selection is underlying mechanism of organic evolution, until recently our studies of evolutionary processes have been confined to the examples from a small plant orbiting an insignificant star in a mid-sized galaxy. From this limited viewpoint we know that evolution is intimately connected with life... but as scientists, we would love to expand the reaches of our database.
The study of synthetic biology was until recently a theoretical science. Engineers, biochemists, and geneticists proposed mechanisms by which molecules and cells could evolve the basic characteristics of life through pathways other than those found on Earth. However, in recent the study of synthetic biology has progressed from a theoretical to an applied science. For example, we already know that it is possible to change the structure of the genetic code in the laboratory (see "Synthetic Life Makes Synthetic Proteins").
Now, researchers at the Scripps Research Institute have demonstrated that RNA molecules can evolve the ability to increase replication efficiency in the lab (see "Artificial Molecules Evolve in the Lab"). Each of these steps brings us one step closer to truly understanding life.
There is little doubt that the work of the researchers at the Scripps Research Institute demonstrates an evolutionary process. However, some will still argue that this is just another lab-based example of evolution, and that we don't really know for sure that the system demonstrated in the lab would work in the "natural" environment.
The true test of whether synthetic biology is a viable demonstration of natural selection will only come when we finally get a glimpse of proto-life on other planets and moons. Europa, Titan, maybe even Mars, may hold "snapshots" of how early chemical evolution occurred.
For too long biologists have focused simply on life on this planet. If we truly want to understand evolution and life, we need to start expanding our horizons.
Comments
I agree completely Michael, I see no problem in using lab based simulations to predict evolutionary trends, but then again my work was on the evolutionary genetics of Drosophila, so I am somewhat biased! So what we need is undeniable evidence, and that, I believe, can only be found elsewhere in the solar system.
Michael Windelspecht | 01/18/09 | 11:41 AM
ehsanul (not verified) | 01/21/09 | 00:26 AM
ehsanul (not verified) | 01/21/09 | 00:36 AM
good points. I never meant it to sounds as if I don't agree with lab-based simulations of evolution - the majority of my own research has been lab-based. My point was meant to be that critics of evolution have often pointed at lab versus natural models (not that this is a valid point!).
As for alien life... I believe that we should be looking for proto-life .... examples of evolutionary processes frozen in time on some of the moons of the solar system. These discoveries would really assist in the development of robust evolutionary studies.
As for alien life... I believe that we should be looking for proto-life .... examples of evolutionary processes frozen in time on some of the moons of the solar system. These discoveries would really assist in the development of robust evolutionary studies.
Michael Windelspecht | 01/21/09 | 14:33 PM









That argument will ring hollow once researchers can generate live cells de novo from non-living components. Self-replicating RNA and Jack Szostak's proto-cells don't quite make that step, obviously. Once that step is made, it will be much harder for people to argue that life can't evolve from non-life. If it can happen in the lab, then it can happen under the right conditions in nature.
But I agree with you that the searching for life on other planets could be interesting (if it's successful), and it has the potential to test the generality of some of our ideas about evolution.