H00102--00A, Front mat Genesis

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by Charles Baum


  p. xvi

  James Trefil: Hazen and Trefil (1991), Trefil and Hazen (1992).

  p. xvii

  “the unfolding of life . . . ”: Morowitz (2002, p. 84).

  p. xvii

  conference in Modena, Italy: The “Workshop on Life” was held

  September 3–8, 2000, as one of the satellite meetings before the Millennial

  World Meeting of University Professors in Rome, September 8–10. The con-

  ference proceedings are collected in Pályi et al. (2002).

  PROLOGUE

  p. 1

  This idea had received a boost: Corliss et al. (1979, 1981). See

  Chapter 7 for more details on Jack Corliss’s controversial claims.

  p. 2

  Morowitz’s dense tabulation: The table of water’s dielectric con-

  stant as a function of temperature and pressure came from Tödheide (1972,

  Table XI, p. 492). See also Uematsu and Franck (1981), Franck (1987), Shaw

  et al. (1991), and Franck and Weingartner (1999) for subsequent measure-

  ments by the same group at the Institute for Physical Chemistry and Elec-

  trochemistry, University of Karlsruhe. In spite of our surprise at seeing these

  results, experts in petroleum chemistry had long known about water’s dis-

  tinctive changes in properties at elevated temperature and pressure (e.g.,

  Simoneit 1995). Theorist Everett Shock had incorporated these effects into

  his calculations of hydrothermal reactions relevant to prebiotic chemistry

  247

  248

  GENESIS

  (Shock 1990a, 1990b, 1992a, 1993; Shock et al. 1995). Nevertheless, few re-

  searchers in the origin-of-life community had made this connection, and no

  relevant experiments had been performed at high temperature and pressure.

  p. 2

  detailed chemical scenario: Wächtershäuser (1988a, 1990a,

  1992). His work is reviewed in Chapters 8 and 15.

  p. 3

  His name provided: A perspective on Harold Morowitz’s contri-

  butions to the founding of astrobiology is provided by Dick and Strick (2004,

  pp. 61-65).

  p. 4

  Hat’s pressure lab: The apparatus and its operation is described

  in Yoder (1950).

  p. 8

  “Humpane”: Jack Szostak writes, “It’s the normal result to obtain

  a mess of hundreds of compounds. The central problem of prebiotic chem-

  istry is how to avoid the universal tar of organic chemistry, and channel the

  chemistry into the products needed for the origin of life.” [Jack Szostak to

  RMH, 21 August 2004]

  1

  THE MISSING LAW

  p. 11

  “It is unlikely . . . ”: J. H. Holland (1998, p. 3).

  p. 11

  Two great laws: Von Baeyer (1998) provides a history of the laws

  of thermodynamics.

  p. 12

  The discovery of a dozen: For a review of the principal laws of

  nature and their discovery, see Hazen and Trefil (1991).

  p. 12

  scholars of the late nineteenth century: The history of the idea

  that science has learned everything of significance appears in Horgan (1996),

  who defends and amplifies the idiotic claim.

  p. 12

  Ilya Prigogine: Prigogine’s influential analyses of emergent sys-

  tems, which he called “dissipative systems,” appears in his books Order Out

  of Chaos: Man’s New Dialogue with Nature (Prigogine 1984) and Exploring Complexity: An Introduction (Nicolis and Prigogine 1989). Of special interest to Prigogine were patterns that arise spontaneously in a shallow pan of

  boiling water (Bénard cells) and in certain types of slowly reacting chemicals

  (Belousov–Zhabotinski, or B–Z, systems). These systems, which could be

  analyzed with mathematical rigor, are representative of a larger class of phe-

  nomena in which energy flows through a collection of interacting particles.

  In the words of Wicken (1987, p. 5), “dissipation through structuring is an

  evolutionary first principle.”

  p. 13

  complex, turbulent convection: The peculiar behavior of boil-

  ing water is addressed, for example, in Nicolis and Prigogine (1989, pp.

  8-15).

  NOTES

  249

  p. 14

  patterns in water and sand: An extensive technical literature

  analyzes the formation of sand patterning. Of special note are the classic

  works of Ralph Bagnold (1941, 1988).

  p. 14

  understanding such simple systems: Several reviewers question

  the idea that studies of patterning in simple mechanical systems such as

  sand can elucidate the behavior of much more complex biological systems.

  Graham Cairns-Smith writes: “I think that your discussion of emergent sys-

  tems could do with a more explicit reference to the two main ways in which

  interestingly complex systems arise in biology—development and evolution.

  Development is modeled by, say, the Mandelbrot set: an amazing infinitely

  complex product with a childishly simple specification. And incidentally I

  don’t see any new physical law here, just mathematics.” (G. Cairns-Smith to

  RMH, 31 August 2004).

  Jack Szostak echoes this opinion: “Part of the problem is the lack of a

  clear definition or understanding of what we mean by emergent phenom-

  ena, which leads to people referring to distinct things with the same term.

  So, in one sense, phenomena such as vortices or sand ripples are ‘emergent’

  since they are collective phenomena not exhibited by the individual compo-

  nents of the system. On the other hand, there seem to be different kinds of

  phenomena one could also call ‘emergent’. . . . Darwinian evolution emerges

  from the combination of replicating informational polymers and compart-

  mentalization.” [Jack Szostak to RMH, 21 August 2004] In other words, some

  scientists argue that emergent systems that become complex through a com-

  petitive selection process are fundamentally different from those that obey

  simple rules of interaction.

  I’m more inclined to think that all emergent systems, whether shifting

  sand dunes or biological evolution, may ultimately be modeled based on a

  small set of “selection rules” reducible to mathematical statements. Ulti-

  mately, evolution through competitive selection represents simply another

  (though admittedly more elaborate) way that systems tend toward the most

  efficient way to dissipate energy.

  p. 15

  A small band of scientists: The Santa Fe Institute and its studies

  in emergence are discussed in Waldrop (1992) and Regis (2003).

  p. 15

  John Holland: Holland’s influential works include Hidden Or-

  der (J. H. Holland 1995) and Emergence: From Chaos to Order (J. H. Holland 1998).

  p. 15

  BOIDS: This program is available at www.red3d.com/cwr/boids.

  The program tracks the flocking behavior of a hundred or so “BOIDS,” each

  of which moves according to three rules: separation to avoid crowding

  flockmates, alignment to follow the flock’s average direction, and cohesion

  to steer toward the average position of flockmates.

  250

  GENESIS

  p. 15

  Physicist Stephen Wolfram: Wolfram (2002).

  p. 16

  Danish physicist Per Bak: Bak’s most ac
cessible writings are

  found in his popular book, How Nature Works: The Science of Self-Organized

  Criticality (Bak 1996).

  p. 16

  Santa Fe theorist Stuart Kauffman: Kauffman (1993).

  p. 16

  Nobel Laureate Murray Gell-Mann: Gell-Mann and Tsallis

  (2004). Ideas of non-extensive entropy and related definitions of complexity

  are provided by Lopez-Ruiz et al. (1995), Shiner et al. (1999), Gell-Mann and Lloyd (2004), Latora and Marchiori (2004), Plastino et al. (2004). See

  also Gell-Mann (1994, 1995).

  p. 17

  fossil-rich hundred-foot-tall cliffs: The Miocene formations of

  Calvert County, Maryland, have been a Mecca for fossil collectors for two

  centuries. Details of the geology and paleontology are recorded in W. B. Clark

  (1904).

  p. 17

  Factor 1: The relationship between concentration of agents and

  complexity has the qualitative form of the so-called error function. This

  function begins at zero complexity for low concentrations of agents. As the

  p. 17

  The relationship between the concentration of interacting agents in a system

  ( N) and the complexity of the system ( C) has the qualitative form of the error function. At low N, no emergent structures arise, but as N increases, so does C, to an upper limit.

  NOTES

  251

  concentration rises, it reaches some critical value, and complexity begins to

  rise. Eventually, at a higher concentration of agents, the system’s complexity

  achieves a maximum value.

  p. 19

  One ant species: Camazine et al. (2001, pp. 256-283). [Also E. O.

  Wilson to RMH, 9 April 2004; B. Fisher to RMH, 5 May 2004; C. W.

  Rettenmeyer to RMH, 12 May 2004]

  p. 19

  Studies of termite colonies: Solé and Goodwin (2000, p. 151).

  p. 19

  spiral arm structure: The formation of spiral arms requires “a

  central mass and a velocity large enough to produce a significant shear. . . .

  You also need time for the patterns to be established. The low mass objects

  don’t survive long enough.” [Vera Rubin to RMH, 7 April 2004]

  p. 19

  Factor 2: I suspect that one of the principal difficulties in quan-

  tifying emergent complexity is related to the varied ways that agents may be

  interconnected. The shifting interactions by immediate contacts of adjacent

  sand grains are not easily equated to the persistent chemical markers of mov-

  ing ants or the elaborate networks of variable impulses that connect neu-

  rons. Nor are any of these examples exactly analogous to the interactions of

  molecules necessary for the origin of life.

  p. 19

  A rounded grain: Bagnold (1941, p. 85).

  p. 20

  The conscious brain: See, for example, Johnson (2001).

  p. 20

  Factor 3: The relationship between energy flow and complexity

  bears a qualitative similarity to a bell-shaped curve. At low energy flux, no

  patterning occurs and the complexity is zero. At some minimum energy flux,

  pattern formation begins and complexity quickly achieves a maximum value.

  Above a critical value, however, the energy flux is too great and the emergent

  patterns begin to disperse.

  p. 20

  no pattern can emerge: Physicist Paul C. W. Davies examines

  this issue from the standpoint of gravity, which is the initial and ultimate

  source of ordering in the universe (Davies 1999, p. 64).

  p. 21

  Factor 4: Cycling may be important in origin-of-life scenarios,

  but the imposition of any kind of cycle adds at least two new variables to an

  experiment. In the case of a temperature cycle, for example, one must select

  the duration of the cycle (typically on the order of minutes to days) and the

  two end-point temperatures. It may also be desirable to control the rate of

  temperature change (gradual versus abrupt), which adds additional vari-

  ables. Needless to say, such added variables complicate an experiment and

  its interpretation.

  p. 22

  amazing stone circles: Kessler and Werner (2003).

  p. 22

  ∇ E( t): This expression indicates both the flow of energy through the system, ∇ E, and the cycling of that energy, which is a function of time, t.

  252

  GENESIS

  At intermediate ∇E, the

  maximum complexity

  emerges

  C

  At high ∇E,

  all patterns

  are destroyed

  At low ∇E, no

  patterns arise

  ∇E

  p. 20

  The relationship between the energy flowing through a system of interacting

  agents (∇ E) and the complexity of the system ( C) has the form of a critical curve. At low ∇ E, no emergent structures arise, but as ∇ E increases above a critical value, structure rapidly appears and C increases. At high ∇ E, however, patterns are destroyed.

  2

  WHAT IS LIFE?

  p. 25

  “I know it when I see it.”: Associate Justice Potter Stewart of the

  U. S. Supreme Court made this statement as part of his concurring opinion in the 6-3 ruling that overturned the ban on pornographic films, June 22,

  1964: “I shall not today attempt further to define the kinds of material . . .

  but I know it when I see it.”

  p. 25

  A recent origin-of-life text: Lahav (1999, pp. 117-121).

  p. 25

  “What is life?”: Pályi et al. (2002).

  p. 26

  “top-down” approach: Jack Szostak states “I don’t think the ear-

  liest fossils tell us anything about life’s earliest chemistry. These fossils are all quite sophisticated organisms.” [Jack Szostak to RMH, 21 August 2004]

  Gustaf Arrhenius echoes this view: “The most ‘primitive’ organisms that we

  can lay our hands on are already hopelessly sophisticated biochemically; they

  are more like us than anything original.” [Gustaf Arrhenius to RMH, 23 De-

  cember 2004]

  NOTES

  253

  Indeed, a principal discovery of Precambrian paleontology is that mod-

  ern-type cells have populated Earth for at least 80 percent of its history. The

  window for life’s emergence is correspondingly brief.

  p. 27

  “working definition”: See Joyce (1994).

  p. 28

  thin molecular coating: The idea of “flat life” has been explored

  by Wächtershäuser (1988a, 1992) among others. For more details see Chap-

  ter 15.

  p. 28

  Claude Lévi-Strauss: Lévi-Strauss, the founder of structural an-

  thropology, argued that all humans share similar patterns of thought. His

  analysis of myths from various cultures, for example, stresses the common

  reliance on dichotomies in dealing with our role in the cosmos. See Lévi-

  Strauss (1969, 1978).

  p. 28

  neptunists, . . . plutonists: This debate, as well as that between

  catastrophists and uniformitarianists, was fueled by a conflict between sci-

  entific and religious interpretation of natural history. See, for example,

  Rudwick (1976) and Laudan (1987).

  p. 29

  “The unfolding of life . . . ”: Morowitz (2002, p. 84). Several

  other authors, notably Christian de Duve (1995a), have adopted a similar
/>   framework of sequential episodes in life’s emergence. See also Davies (1999),

  Maynard-Smith and Szathmáry (1999), and Bada (2004).

  p. 30

  semantic question: For a fuller explanation of these ideas, see

  Hazen (2002). Jack Szostak writes: “I used to think of the transition from

  non-life to life as a discontinuous event marked by the sudden start-up of

  Darwinian evolution. But as I’ve started to work on more aspects of the

  problem and look at it in more detail, what I see is more of a series of smaller

  steps.” [Jack Szostak to RMH, 7 September 2004]

  p. 30

  philosopher Carol Cleland: Cleland and Chyba (2002).

  p. 31

  Saturn’s recently visited moon: Evidence for volatiles at Titan’s

  surface are presented by Lunine et al. (1999), Campbell et al. (2003), Griffith

  et al. (2003), and Lorenz et al. (2003). For the latest results from the Huygen’s

  probe, see: http://saturn.jpl.nasa.gov/home/index.cfm.

  3

  LOOKING FOR LIFE

  p. 33

  “Scientists turn reckless . . . ”: Lightman (1993, p. 41).

  p. 33

  meteorite from Mars: For an overview of Martian meteorites

  and their identification see McSween (1994). Goldsmith (1997) provides a

  popular account of the Allan Hills controversy.

  p. 33

  Theorists maintained: Calculations by Jay Melosh and co-workers

  of Caltech (Melosh 1988, 1993; Head et al. 2002) reveal that, although a lot

  of material is vaporized in large planetary impacts, rocks at the periphery of

  254

  GENESIS

  the impact site may be hurled unscathed off the surface into space. Such a

  process is thought to have transferred material from Mars to Earth. Similar

  impacts on Earth have certainly blasted terrestrial rocks into space, though

  the transfer of Earth rocks to Mars is much more difficult because of two

  gravitational impediments: Mars is much farther from the Sun, and it has a

  smaller gravitational field.

  An alternative intriguing hypothesis is that cellular life may have arisen

  very early in Earth’s history, and that some of these microbes may have been

  blasted into space by large asteroid impacts. Even if a subsequent globe-

  sterilizing giant impact occurred, life could have been reseeded by an Earth

  meteorite.

  p. 33

  Allan Hills region of Antarctica: The ice deserts of Antarctica

  are ideal hunting grounds for meteorites. These clean, dry regions persist for

  thousands of years, and dark-colored meteorites stand out starkly against

 

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