December 11, 2006 | David F. Coppedge

Darwinists Award New Inductee

The journal Science published the winning entry in the 2006 contest “GE and Science Prize for Young Life Scientists.”  The Grand Prize went to Irene A. Chen (Harvard) for her essay entitled, “The Emergence of Cells During the Origin of Life.”1  Her chemical-evolution scenario makes generous use of that word emergence and its synonyms.

Modern living organisms are organized into cells.  Fundamentally, a cell consists of a genome, which carries information, and a membrane, which separates the genome from the external environment.  By segregating individual genomes from one another, cellular organization is thought to be critical to the evolution of replicating systems.  Some of the oldest known rocks on Earth (~3.5 billion years old) contain biochemical signatures of life and also contain tantalizing suggestions of cellular fossils.  But how did early self-replicating chemicals give rise to the “cell” as a unified entity?  The combination of a genome and membrane does not constitute a unified cell unless interactions between the components result in mutual benefit.  Was it a lucky accident that genomes and membranes began to cooperate with each other (e.g., evolution of an enzyme to synthesize membrane lipids)?  Or are there simple physicochemical mechanisms that promote interactions between any genome and membrane, leading to the emergence of cellular behaviors?  We explored such mechanisms experimentally, using model protocells.

Her essay dealt with the possibility of a “self-replicating genome inside a chemically simple, self-replicating membrane” that would be akin to “early evolution” by natural selection at the level of molecules.  She spoke of “membrane fitness (i.e., growth)” in a process that ostensibly gets away from chance, because the fat globules are observed to grow in solution according to a kind of survival of the fittest.  Apparently Darwinian selfishness got started early on:

We suggest that a similar process took place during early evolution–vesicles encapsulating highly active genomic replicators would generate osmotic pressure, causing them to “steal” membrane from other vesicles containing less active sequences.  Genomic fitness (i.e., replicative ability) would be translated into cellular fitness as the genome and membrane increased together, moving the evolutionary unit from the replicating molecule to the whole cell.  As soon as replicators became encapsulated, a primitive form of competition could emerge between cells (see the figure).  Remarkably, this process does not require a chance increase in complexity (e.g., addition of a new enzyme), but instead relies only on the physical properties of a semipermeable membrane encapsulating solute.

Her paper even suggested avenues for further research.  For instance, a charged genetic molecule might be found to be more effective at stealing membrane lipids.  “Could this influence the natural selection of the genetic material itself?”, she asks.  Once the membrane competition settles down, however, the dynamics would also decrease.  This is not a problem, she indicates, because by now, genetic evolution has mastered the art of innovation: “evolutionary solutions to this problem (e.g., permeases, synthetic enzymes) could cause a ‘snowball’ effect on the complexity of early life.”  Geophysic’s inability is Darwin’s opportunity, so to speak.  She spoke of information in the genome, but did not attempt to explain where the information comes from.2  Except for one brief suggestion that charged RNA might have some unspecified advantage gaining membrane lipids, she also did not discuss how a genetic takeover of the “membrane fitness” might have occurred.3
    Other entries that lost out on the Grand Prize included one called “Unraveling the Mysteries of Small RNAs,” another on “Photosystem II, a Bioenergetic Nanomachine.”

1Irene A. Chen, “The Emergence of Cells During the Origin of Life,” Science, 8 December 2006: Vol. 314. no. 5805, pp. 1558 – 1559, DOI: 10.1126/science.1137541.
2The information in DNA is described in the film Unlocking the Mystery of Life as “the most densely compact and elaborately detailed assemblage of information in the known universe.”  The new film The Case for a Creator says that the genetic information for all animal life would fit into a teaspoon, with room left over for all the books in the world ever written.  Dr. Dean Kenyon described the information density of DNA in the bonus features of the film Where Does the Evidence Lead? as a quintillion bits per cubic millimeter.  Transferred onto man’s digital media, that much information would produce a stack of DVDs over six times the height of Mt. Everest.
3At some point, the genome would need to direct the construction of the membrane and control traffic going in and out.  In addition, this genome would need the capability of reproducing itself – and all the parts of the cell – with a high degree of accuracy.  Living cells today have elaborate networks of enzymes, channels, gates, and molecular machines involved in all these processes.  For more on the implausibility of genetic takeovers, see 01/28/2005 and 11/25/2004.

Well, Irene has the vocabulary down: emergence, tantalizing suggestions (12/22/2003), simple physicochemical mechanisms that lead to emergence of complexity, and on and on anon.  The only “snowball effect” was her snow job on the judges.  We’ve dealt with the problems of the fatbubble theory (09/03/2004) and the RNA world (07/11/2002) and other leading scenarios at length elsewhere so many times (follow the Chain Links on Origin of Life), it would be superfluous to repeat them here (sample, 02/15/2004).  This young lady did a pretty good job of disgracing her mind without our help.
    Why did other contestants lose out?  Simple; they wrote about nanomachines and networks and photosynthesis – things that sound like intelligent design.  With the Visigoths at the gates (05/06/2006), the Darwin Priests needed to reassure the peasants by showcasing another inductee into the Temple Prostitutes, to show that the cult of Tinker Bell under King Charlie continues unthreatened.  Sad to see another promising young scientist fall under the spell (see next commentary). 

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Categories: Dumb Ideas, Origin of Life

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