Vincent J. Curtis
16 May 11
Dr. David Deamer presented a lecture on May 10, 2011, entitled “Systems Biology, Synthetic Biology, and the Origin of Life” that was held in the Michael Degroote Center of Learning on the campus of McMaster University.
Dr. Deamer is a professor of biomolecular engineering at the University of California at Santa Cruz. He is presently the Dr. Harry Lyman Hooker distinguished visiting professor at McMaster University, and presented this public lecture on behalf of the Origins Institute. Dr. Deamer lists his research interests as the processes by which cellular life arose on the earth nearly four billion years ago.
The lecture was presented to approximately fifty people, most of whom were middle aged or older. The lecture itself was presented in an elevated fashion appropriate for intelligent people somewhat knowledgeable on the subject. It did not become a hard core technical presentation rich in jargon and digestible only by his doctoral students. A pleasant and soft spoken gentleman, Dr. Deamer gave a lucid presentation that never attempted to hide or gloss over the weaknesses of the theory. He allowed the listener to reach his own conclusions.
The current theory as presented by Dr. Deamer can be summarized briefly: after the formation of the earth, pre-formed organic matter fell from the heavens. Then, after a succession of miracles, pre-biotic lipid-protein structures self-assembled, and these exhibited some of the properties of life.
The further step, from self-assembled lipid-protein structures to a cell which self-replicates and responds to stimuli, – another miracle - was not discussed in the lecture.
The present theory of the origin of life on earth does not hold that DNA came first, but rather that life began by the spontaneous creation of cell-like structures that included membranes as well as DNA.
The way Dr. Deamer used the term ‘self-assembled’ in his lecture was inaccurately suggestive. Self-assembly is not the same thing as self-reproduction. Water molecules could be said to self-assemble into the material we call ice, upon the removal of heat. The example Dr. Deamer used was of soap bubbles being the product of ‘self-assembling’ soap molecules. The phenomenon of soap bubbles, however, is well understood by the science of the thermodynamics of surfaces. The molecules in the bubble assemble the way they do not from anything originating in ‘self’ but from the minimization of the Gibbs Free Energy of the system. Though fun, there is nothing particularly wondrous about the formation of bubbles, for soap bubbles are not self-reproducing. When he says that soap molecules are ‘self-assembling’, Deamer suggestively places the efficient cause of bubble formation in the wrong place. Soap molecules are the material cause of soap bubbles; minimization of the Gibbs Free Energy is the efficient, and perhaps the final, cause. Living things are the efficient cause of their own reproduction.
The current theory of the earth’s formation holds that it formed as an accretion of material from the cloud of matter that eventually condensed into the solar system we presently know, with a star at the center, and planets and asteroids orbiting around it. Because of the early conditions of accretion, any organic matter on earth during this period would have been destroyed. Thus it would have to be after the earth had substantially formed that pre-formed organic matter falling on meteors from space to the earth provided the necessary starting material for cells to form.
The reason why preformed organic matter is necessary to the formation of cells is that something is necessary to provide the vesicles in which the first primitive cells on earth could organize. The example Dr. Deamer used was caprylic acid, an eight carbon, linear carboxylic acid. On the surface of water this acid appears to form vesicle-like structures. Dr. Deamer theorized that organic matter like that found on meteorites today fell to earth approximately four billion years ago and carried on them the precursor material necessary for the beginning of life on earth.
The word miracle is used here as a shorthand for a highly improbable event that needs to have occurred only once.
The problem with requiring the event to only occur once is that it removes the proposition from the realm of science. Science is concerned with the reproducible, and something that only occurs once is not reproducible. Yet to require an event to happen reproducibly raises the question of why is it not happening now? Why is life not originating from dead matter now? Thus the theory also requires that the process by which life originated, if it is reproducible, was destroyed by the present existence of life.
Experiments which attempt in five years to reproduce the origins of life that occurred over a span of 100 million years on earth raises the problem that the experimenter is acting as an “intelligent designer,” as was pointed out by one of the spectators.
These experiments which attempt to reproduce the beginning of life usually start with ammonia as part of the mix of precursor materials. The trouble is that ammonia, or ‘fixed nitrogen’ as chemists call it, is the product of bacterial activity. Mankind only figured out how to fix nitrogen at the beginning of the 20th century, and so how an abundance of ammonia could be present before life began on earth is something that needs explaining.
Caprylic acid, which Dr. Deamer uses as an example of a molecule which self-assembles into vesicles under certain conditions, is also a product of biological activity. A linear, eight carbon, terminal carboxylic acid does not occur in naturally when graphite, hydrogen, and oxygen are present together. The organic matter that started life on earth had to come, according to the theory, from life that existed previously on other planets in other solar systems. The theory of the origin of life on earth thus fails to answer the question of why life began at all. It punts the question, saying it began somewhere else.
When asked if the theory he presented, however improbable, must be the way life originated on earth, Dr. Deamer said that there were other theories, one of which was that entire life forms were carried to earth on meteors, not just lifeless organic matter. Thus the present theories of the original of life on earth fail the answer the more basic question of why life began at all.
Another scientific failing of the theories that life began elsewhere is that they set up an infinite regress even though the life of the universe is finite. The universe is approximately 13 billion years old, and the life of the earth is 4.5 billion. Because the elements carbon, oxygen, nitrogen, phosphorus, and sulphur on earth are the products of a supernova, a star which formed these elements from hydrogen in the course of its life and then exploded, the earth is a second generation accretion of matter since the beginning of the universe.
A minimum of three solar generations are required to produce life on earth according to the theory: the first generation produced the carbon required for life, the second produced the first generation of living matter from that carbon of the first supernova, and then in the third generation the residual organic matter of the second generation fell to the earth four billion years ago after a second supernova destroyed the solar system containing the first life. If the lifespan of a large star is six billion years, then the universe would have to be a minimum of 15 or 16 billion years old for this sequence to have occurred, not 13 billion.
The current theories on the origin of life on earth are highly unsatisfactory from the scientific point of view. It would not be inaccurate to say that they merely put a scientific gloss to the concept of a miracle.
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