Claim CB010.2:
The most primitive cells are too complex to have come together by chance.
(See also Probability of abiogenesis.)
Source:
Watchtower Bible and Tract Society. 1985. Life--How Did It Get Here?
Brooklyn, NY,
pg. 44.
Morris, Henry M. 1985. Scientific Creationism. Green Forest, AR:
Master Books,
pp. 59-69.
Response:
- Biochemistry is not chance. It inevitably produces complex products.
Amino acids and other complex molecules are even known to form in
space.
- Nobody knows what the most primitive cells looked like. All the cells
around today are the product of billions of years of evolution. The
earliest self-replicator was likely very much simpler than anything
alive today; self-replicating molecules need not be all that complex
(Lee et al. 1996), and protein-building systems can also be simple
(Ball 2001; Tamura and Schimmel 2001).
- This claim is an example of the argument from
incredulity.
Nobody denies that the origin of life is an extremely difficult
problem. That it has not been solved, though, does not mean it is
impossible. In fact, there has been much work in this area, leading to
several possible origins for life on earth:
- Panspermia, which says life came from someplace other than earth.
This theory, however, still does not answer how the first life arose.
- Proteinoid microspheres (Fox 1960, 1984; Fox and Dose 1977; Fox et
al. 1995; Pappelis and Fox 1995): This theory gives a plausible
account of how some replicating structures, which might well be
called alive, could have arisen. Its main difficulty is explaining
how modern cells arose from the microspheres.
- Clay crystals (Cairn-Smith 1985): This says that the first
replicators were crystals in clay. Though they do not have a
metabolism or respond to the environment, these crystals carry
information and reproduce. Again, there is no known mechanism for
moving from clay to DNA.
- Emerging hypercycles: This proposes a gradual origin of the first
life, roughly in the following stages: (1) a primordial soup of
simple organic compounds. This seems to be almost inevitable; (2)
nucleoproteins, somewhat like modern tRNA (de Duve 1995a) or peptide
nucleic acid (Nelson et al. 2000), and semicatalytic; (3)
hypercycles, or pockets of primitive biochemical pathways that
include some approximate self-replication; (4) cellular hypercycles,
in which more complex hypercycles are enclosed in a primitive
membrane; (5) first simple cell. Complexity theory suggests that the
self-organization is not improbable. This view of abiogenesis is the
current front-runner.
- The iron-sulfur world (Russell and Hall 1997;
Wächtershäuser 2000): It has been found that all the steps
for the conversion of carbon monoxide into peptides can occur at high
temperature and pressure, catalyzed by iron and nickel sulfides.
Such conditions exist around submarine hydrothermal vents. Iron
sulfide precipitates could have served as precursors of cell walls as
well as catalysts (Martin and Russell 2003). A peptide cycle, from
peptides to amino acids and back, is a prerequisite to metabolism,
and such a cycle could have arisen in the iron-sulfur world (Huber et
al. 2003).
- Polymerization on sheltered organophilic surfaces (Smith et al.
1999): The first self-replicating molecules may have formed within
tiny indentations of silica-rich surfaces so that the surrounding
rock was its first cell wall.
- Something that no one has thought of yet.
Links:
Robinson, Richard. 2005. Jump-starting a cellular world: Investigating
the origin of life, from soup to networks. PLoS Biology 3(11): e396.
http://biology.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pbio.0030396
References:
- Ball, Philip. 2001. Missing links made simple. Nature Science
Update (15 Mar.). http://www.nature.com/nsu/010308/010308-5.html
- Cairn-Smith, A. G. 1985. Seven Clues to the Origin of Life,
Cambridge University Press.
- de Duve, Christian. 1995a. The beginnings of life on
earth. American Scientist 83: 428-437.
http://www.americanscientist.org/template/AssetDetail/assetid/21438?fulltext=true
- Fox, S. W. 1960. How did life begin? Science 132: 200-208.
- Fox, S. W. 1984. Creationism and evolutionary protobiogenesis. In:
Science and Creationism, ed. A. Montagu, Oxford
University Press, pp. 194-239.
- Fox, S. W. and K. Dose. 1977. Molecular Evolution and the Origin of
Life, Revised ed. New York: Marcel Dekker.
- Fox, S. W. et al. 1995. Experimental retracement of the origins of a
protocell: It was also a protoneuron. In Ponnamperuma, C. and J.
Chela-Flores, pp. 17-36.
- Huber, Claudia, Wolfgang Eisenreich, Stefan Hecht and Günter
Wächtershäuser. 2003. A possible primordial peptide cycle.
Science 301: 938-940.
- Lee, D. H. et al. 1996. A self-replicating peptide. Nature 382:
525-528.
- Martin, W. and M. J. Russell. 2003. (see below)
- Nelson, Kevin E., M. Levy and S. L. Miller. 2000. Peptide nucleic acids
rather than RNA may have been the first genetic molecule. Proceedings of
the National Academy of Science USA 97:
3868-3871.
- Ponnamperuma, C. and J. Chela-Flores (eds.). 1995. Chemical
Evolution: Structure and Model of the First Cell. Dordrecht: Kluwer
Academic Publishers.
- Pappelis, A. and S. W. Fox. 1995. Domain protolife: Protocells and
metaprotocells within thermal protein matrices. In Ponnamperuma, C. and
Chela-Flores, pp. 129-132.
- Russell, M. J. and A. J. Hall. 1997. The emergence of life from iron
monosulphide bubbles at a submarine hydrothermal redox and pH front.
Journal of the Geological Society of London 154: 377-402.
http://www.gla.ac.uk/Project/originoflife/html/2001/pdf_articles.htm
- Smith, J. V., F. P. Arnold Jr., I. Parsons, and M. R. Lee. 1999.
Biochemical evolution III: Polymerization on organophilic silica-rich
surfaces, crystal-chemical modeling, formation of first cells, and
geological clues. Proceedings of the National Academy of Science
USA 96(7): 3479-3485.
http://www.pnas.org/cgi/content/full/96/7/3479
- Tamura, K. and P. Schimmel. 2001. Oligonucleotide-directed peptide
synthesis in a ribosome- and ribozyme-free system. Proceedings of the
National Academy of Science USA 98: 1393-1397.
- Wächtershäuser, Günter. 2000. Life as we don't know
it. Science 289: 1307-1308.
Further Reading:
Fry, Iris. 2000. The Emergence of Life on Earth: A Historical and
Scientific Overview. New Brunswick, NJ: Rutgers University Press.
Cohen, Phil. 1996. Let there be life. New Scientist 151 (6 July):
22-27. http://www.newscientist.com/hottopics/astrobiology/letthere.jsp
de Duve, Christian. 1995a.
(see above)
de Duve, Christian. 1995b. Vital Dust: Life as a cosmic
imperative.
New York: Basic Books.
Fox, S. 1988. The Emergence of Life: Darwinian Evolution from the
Inside. New York: Basic Books.
Lacey, J. C., N. S. Wickramasinghe, and G. W. Cook. 1992. Experimental
studies on the origin of the genetic code and the process of protein
synthesis: A review update. Origins of Life and Evolution of the
Biosphere 22(5): 243-275. (technical)
Lewis, Ricki. 1997. Scientists debate RNA's role at beginning
of life on earth. The Scientist 11(7) (31 Mar.): 11.
http://www.the-scientist.com/yr1997/mar/research_970331.html
(registration required), or
http://www.mhhe.com/biosci/genbio/life/articles/article28.mhtml
Martin, W. and M. J. Russell. 2003. On the origins of cells: A hypothesis
for the evolutionary transitions from abiotic geochemistry to
chemoautotrophic prokaryotes, and from prokaryotes to nucleated cells.
Philosophical Transactions, Biological Sciences 358: 59-85.
(technical)
McClendon, John H. 1999. The origin of life. Earth-Science Reviews 47:
71-93. (technical)
Orgel, L. E. 1994. The origin of life on the earth. Scientific
American 271(4) (Oct):
76-83.
Pigliucci, Massimo. 1999. Where do we come from? a humbling look at the
biology of life's origin. Skeptical Inquirer 23(5): 21-27.
Russell, Michael. 2003. Evolution: Five big questions: 1. How
did life begin? New Scientist 178(2399) (14 June): 33-34.
Willis, Peter. 1997. Turning a corner in the search for the origin of
life. Santa Fe Institute Bulletin 12(2).
http://www.santafe.edu/sfi/publications/Bulletins/bulletin-summer97/turning.html
created 2001-3-31, modified 2005-12-14