At this point, the case for evolutionary progress in a biologically closed system depends heavily on the remotest evidence of all, the new perfect barrier to life, the big bang. If the whole universe is a permanently closed system that began in a lifeless state a finite time ago, then evolutionary progress, including the origin of life, must have subsequently happened in it. But the big bang theory is plagued with frequent surprises (e.g. Glanz, 1998). In some versions, big bangs are preceded by other big bangs ad infinitum (Guth, 1997), and ways for life to persist through big bangs have been proposed (Frautschi, 1982; Krauss and Starkman, 1999). In any case, to understand evolutionary progress biology should be able to cite firmer and more immediate evidence than the big bang!
With its basis insecure and under revision, and with an alternative becoming apparent, the theory that life makes evolutionary progress in a closed system needs additional support.
Computers, like life, rely on encoded instructions. They also exhibit evolutionary progress. Accumulated improvements have made commercial software far more powerful today than only fifteen years ago. Of course, this evolution has occurred in an open system, because people installed the improvements. But computer experiments that attempt to model evolutionary progress in closed systems are under way (e.g. Ray, 1996). The work is called "artificial life" and various other names, and the experimental environment is not restricted to conventional software. Obviously, a closed-system model that exhibited lifelike, sustained evolutionary progress would have profound importance for biology. In fact, many closed-system computer models exhibit surprising behavior or solve preestablished problems. But in spite of much honest effort, none has achieved ongoing, open-ended evolutionary progress. They all remain confined within their original parameters.
Nevertheless, computer scientists are confident that an unquestionable demonstration of evolutionary progress in artificial life is imminent, because they think they are only trying to model a phenomenon already proven in biology. Many biologists, on the other hand, are under the impression that computer models have already corroborated evolutionary progress in a closed system.
Yet the phenomenon has not been unequivocally demonstrated in either medium. Until it is, one can reasonably doubt that evolutionary progress in a closed system is possible, in real or artificial life.
Acknowledgments
The author thanks Max Garzon, Chris Langton and Dan McShea for their advice and encouragement.
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What'sNEW
01 Jan 2020: By 2020, sustainable evolutionary progress, will not have been demonstrated. (Online prediction, 2002.)
08 Apr 2019: Helpful genetic mutations can be induced by environmental stress....
11 Nov 2016: George Church says Prove it.
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10 Dec 2004: Evolution versus creationism was the topic on CNN last week.
26 Nov 2004: The evolution of a new fruitfly gene...
26 Sep 2004: An article promoting Intelligent Design...
19 Jun 2004: Darwinism's ability to produce evolutionary progress has not been demonstrated....
2002, December 31: No evolutionary progress in a closed system!
Scientists exposed as sloppy reporters by Hazel Muir, New Scientist, 14 Dec 2002. Is this how biologists and computer modelers became misinformed?
2002, May 9: Bet on sustainable evolutionary progress?
2001, November 21: The University of Oklahoma will probe for evolutionary progress in closed systems.
2001, October 9: Funds available for research.
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What'sNEW: Lenski et al.
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Rapid Adaptation Often Occurs through Mutations to the Most Highly Conserved Positions of the RNA Polymerase Core Enzyme by Yasmin Cohen and Ruth Hershberg, Genome Biology and Evolution, Sep 2022.
Legendary bacterial evolution experiment enters new era by Ewen Callaway, Nature, 14 Jun 2022.
10 Mar 2021: New genes can be acquired only via HGT....
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20 Sep 2012: Richard Lenski's research group has analysed the evolution of aerobic citrate metabolism among cloned bacteria.
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Welcome to the E. coli Long-term Experimental Evolution Project Site, Richard E. Lenski, Michigan State University.
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23 Feb 2012: Experimenters with a virus and its bacterial host in a quarantined system report a breakthrough.
Hsin-Hung Chou et al., "Diminishing Returns Epistasis Among Beneficial Mutations Decelerates Adaptation" [abstract], doi:10.1126/science.1203799, p1190-1192 v332, Science, 3 Jun 2011.
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29 Apr 2011: An analysis of long-running evolution experiments has been done by biochemist Michael Behe.
13 Apr 2011: Nothing yet. That's what we observe from an experiment at Michigan State University.
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29 Oct 2009: 40,000 generations of E. Coli have been monitored in a long-term experiment.
5 Jun 2008: Cloned bacteria evolved an unexpected feature in a long-running experiment led by Richard Lenski.
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Origin of complex functions? — Brig Klyce's letter to Nature, 17 May, and a response, 22 May 2003.
2003, May 11: Computer model evolves complex functions?
2003, February 4: The latest results from a closed-system biological experiment.
2003, January 26: "Evolving Inventions," in Scientific American.
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Contacting Richard Lenski, in August 2000, was not fruitful.
2000, April 14: Comments from Nobel laureate Joshua Lederberg seem relevant.
1999, September 26: Experimental Evolution with Microbes and Molecules
1999, August 12: New computer model of evolution
1999, July 15: A Recent Issue of Science....