Here I offer more interesting and insightful remarks by Charles Rulon on the question of the origin of life and the issue of synthesizing life in the laboratory.
Origin of life research
By insisting on naturalistic hypotheses instead of falling back on “God did it,” many of the key steps in the transformation from inanimate matter to living cells are now understood in considerable detail. Major discoveries in the past 60 years have already led to creating genetic material, proteins and other biochemical structures that begin to bridge the gap between non-life and life. In fact, some researchers are now in the process of building their own living cells from scratch. Others are slowly filling the gap between their computer models which simulate evolution and the actual biochemistry lab, itself.
Still, many puzzles remain—puzzles that are fuel for God beliefs. A few theistic scientists have written books about the “finger of God” being necessary to bridge the gap between non-life and life. But such theistic arguments, strongly refuted by other scientists, don’t lead to new experiments, so just tend to stop research.
Q. If scientists can’t explain life’s origin, how can they be sure of our evolution?
A. The overwhelming evidence in support of evolution does not come from origin of life experiments, but from the millions of already discovered fossils, genetic analyses, plus numerous other converging lines of solid evidence. As an analogy, just because scientists haven’t made a chicken egg from scratch doesn’t mean that chicken eggs don’t develop into chickens.
Q. Aren’t living cells much too complex to have evolved naturally?
A. First, microscopic fossil evidence indicates that ancient cells were far simpler than most cells found today. Second, and of considerable significance, there never has been a clear-cut distinction between what is obviously alive and what is not. Instead, a continuum exists.
There are viroids which are short circles of genetic material, yet are responsible for over a dozen different plant diseases. There are viruses (genes surrounded by a protein coat), not considered alive because they do not have cells and need a host, yet not exactly dead either, since they have genes, can reproduce, and can evolve through natural selection. These viruses come in all shapes, sizes and levels of complexity. There are even entities called satellites—metaviruses that can replicate only within a virus that is already inside a host cell.
In 1992 there was the discovery of a truly monstrous virus officially known as Mimivirus (because it mimics a bacterium in many ways). This virus has more than 900 genes and is much more genetically complex than all previously known viruses, not to mention a number of parasitic bacteria. With the Mimivirus, the boundary between viruses and bacteria became officially blurred.
There is now considerable evidence that viruses were involved very early on in the evolutionary emergence of life. Most of the genetic material on this planet appears to be viral in origin. Their ability to interact with organisms and to move genetic material around make viruses major players in driving the evolution of new species. Half of all human DNA is believed to have originally come from viruses.
Most living cells today have a nucleus. Some scientists believe that a large DNA-based virus took up residence inside a bacterial cell more than a billion years ago to create the first cell nucleus. If so, all life forms today with nucleated cells may have descended from viruses.
Even so, there still exists an ancient line of microbes known as the archaea, which have no nucleus and may make up as much as one-third of all life on earth.
Q. Isn’t it still possible that God intervened to create life from non-life and even to guarantee our evolution?
A. How is that hypothesis scientifically testable? Besides, even if there were a god somewhere in the origin and evolution of life picture, that still doesn’t mean by any stretch of logic that this god must be the God of the Christians. Maybe this “cosmic being” merely evolved humans as “fast food” for his truly chosen species which is now touring our galaxy.
The basic problem, of course, with all such God beliefs from a scientific perspective is that such beliefs tend to stop research. To glibly say that God did it is merely to give ignorance a name. We’ll never get closer to discovering how life might actually have originated if we keep filling in our gaps in knowledge with “God did it” answers.
What we do know so far is that the scientific evidence currently supports the hypothesis that “life” gradually appeared through an accumulation of genetic typos committed by hordes of mindless microscopic “replication machines”. What we do know is that the more scientists have learned about living things, the clearer it has become that all of life’s processes, from fertilization to the evolution of the human brain, appear to be based entirely on chemical and physical laws. No laws of nature have been bypassed or broken. No extra miracles or “vital forces” seem to be required. It just doesn’t seem necessary (and hasn’t for a long time now) to posit supernatural interventions for the origin of life or for human evolution.
by Charles L. Rulon. Emeritus, Life & Health Sciences
Long Beach City College
Key web sites for progress on the origin of life problem:
In the mid-l950′s Dr. Sidney Fox, a specialist in protein biochemistry at the University of Miami, and his colleagues heated a dry mixture of amino acids. The amino acids automatically hooked together to form chains of from 30 to l00 amino acids long. These “proteinoids,” as Fox named them, were strikingly similar to true proteins and, according to Fox, could have served as the raw material from which life evolved. Not only did protein-like macro-molecules automatically formed from amino acids, but when these proteinoids were exposed to water, they automatically formed little spheres which have many properties similar to today’s cells. There are numerous published researched reports with copious data showing that many modern proteins appear to have derived from a few such ancestral proteins.
By 1993 computer scientists, microbiologists, chemists, physicists, mathematicians and evolutionary theorists had succeeded in creating creatures that looked and acted very much like living organisms. They grew, ate, reproduced, mutated, fought with each other and died—and they did all this spontaneously, without interference or help from their human creators (Levy, S., Artificial Life: The Quest for a New Creation -1993).
By 2010 see Scientific American: http://www.scientificamerican.com/article.cfm?id=the-real-promise-of-synthetic-biologyFollow Craig Venter’s progress: http://biosingularity.wordpress.com/2010/01/31/craig-venter-talks-about-creating-synthetic-life/
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