Customer Reviews

Emergence of Life on Earth: A Historical and Scientific Overview

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From the ancient Greek philosophers through Enlightenment science to today's high-tech world, how life originated has been a compelling question. Fry presents the thinkers and their ideas about this enigma with penetrating skill. Her recapitulation of the philosophical questions set in their historical perspective demonstrates the persistence of many concepts regarding life's history. "Spontaneous generation", now considered a quaint idea, dominated the view of theologians and natural scientists alike. Even when empirical experiments demonstrated the falsity of the notion, versions of it remained, deflecting other proposals.

Fry shows how Darwin's idea of natural selection over vast periods of time allowed tracing a view of life back to simple, microscopic life forms. Darwin's famous "warm little pond" may have been an incomplete picture, but it demonstrated a break with established notions. Complex life evolved from simple life, not fully blown from a soiled shirt. Only in the 20th Century did technology and the discovery of unanticipated life forms in extreme conditions allow a look at the chemical basis of life before complexity could emerge.

Fry carefully and skillfully examines all these steps, giving each thinker his due while placing him in historical context. There's more than one surprise here for those who don't know the lives of researchers such as Pasteur, Eigen or Oparin. As she reveals the progress of thinking on the subject, Fry examines the roots of various proposals, their advances and their shortcomings. Was life's beginning protein-based? Are amino acids the foundation or the product of life? Did RNA precede DNA or the reverse? Science proceeds on a step-by-step basis and Fry describes that halting, but useful process far better than most. While Fry's descriptive prose reflects a thesis style, the wealth of information here overrides that limited criticism.

Among the modern thinkers on life's origins, Fry provides the best summation available on the ideas of two men, Graham Cairns Smith and Gunther Wachtershauser. Both men have offered theories of chemical beginnings of life, the one suggesting clay crystals as replication models, the other utilising the iron-sulfur energy capacity of pyrite. These two concepts are united by Fry in light of the processes found associated with deep sea-floor vents.

Fry's conclusion deals with the likelihood of life on worlds other than Earth. The dispute over whether the Antarctic Martian meteorite exhibits organic residues serves to show how limited current information actually is on pre-life chemistry. More research, more examination and more questions need to be posed. Fry's book provides a solid foundation for the next steps. [stephen a. haines - Ottawa, Canada]

Trained in philosophy, but more than conversant in chemistry and biochemistry, Iris Fry does the scientific community a splendid service in offering this comprehensive and up-to-date look at the scientific work being done on life's origins. She points out that it is ultimately a metaphysical matter, resting on faith--but on faith backed up by the splendid track record of scientific empiricism--that life evolved, most likely on Earth, from inanimate matter. But as you read this detailed and wonderfully referenced work the odds of life appearing otherwise appreciably diminish, and a picture, soberly stated and carefully argued, of a metabolic (pre-genetic) origin prior to genes subtly insinuates itself into your rational consciousness. My favorite part of the work is the reference to Jeffrey Wicken whose critique of Manfred Eigen's hypercyle theory leads me to suggest that a selfish RNA world would no more be likely to encumber its streamlined replicants with bodies than an Olympic sprinter would be to run a three-legged race. I am not sure about her Kantian interpretations and she misses some important work on the origins of life, such as Clifford Matthews hydrogen cyanide world; she also does not (in my opinion) sufficiently ground life's early cyclical processes in cyclical nonequilibrium thermodynamic systems. But you can't have everything--where would you put it?
I love the fact that she is a philosopher and outside the various factions she surveys. This means she has no axe to grind and you can trust her as a fair guide among the competing views which, she points out, will increasingly come together as science moves forward. Best read along with Freeman Dyson's revised, 1999 edition entitled Origins of Life.

This is an excellent overview of the research on the origin of life. It starts with historical material, including the refutation of ancient "spontaneous generation" theories by Pasteur. We then get to the Darwinians. Haeckel in particular felt that inanimate matter made a transition to a living system in an evolutionary manner. In the 1920s, Oparin and Haldane speculated on the organic components and atmosphere that might have been present on the early Earth. And Fry tells us of the Urey-Miller experiment of 1953.

Next we find out about the contributions of Sidney Fox, who suggested a model that started with abiotic material and then generated amino acids, condensed them to form "protenoids," and then formed cell-like "microspheres." This was a "protein-first approach." That is contrasted with the "gene-first approach" and accompanying experiments by Spiegelman, Orgel, and Eigen.

There is a discussion of the "RNA world" and whether or not there was a world of earlier self-replicators. And Fry gives arguments for and against the ideas of Freeman Dyson (with the emphasis on primitive cells), Stuart Kauffman (with the emphasis on "catalytic closure") and Gunter Wachtershauser (with the emphasis on Iron Sulfide chemistry).

Fry is at her best discussing the need to ask if life originated by a series of likely steps, by design, or by one or more unlikely steps. She makes it clear that long required sequences simply can't form by pure chance. There must be some natural ordering (such as in snowflakes) as well as incremental improvement (in an evolutionary manner). And if we are left with some theories that require some incredible luck and some theories that do not require such luck, we'll obviously prefer the latter. She discusses de Duve's ideas here. It seems that a "scaffolding" approach is a good concept, while autocatalytic cycles may be needed almost by definition (of life).

That gets us to the final chapter, where the definition of life is indeed discussed. In addition, Fry talks about the possibility of there having been life on Mars and elsewhere in our solar system. There's also some material about habitable zones, and on the possibility of life on extrasolar planets.

I recommend this book.

I've read many books on this theme,but I rarely came across a treatise so complete,so vast in scope ans so profound and well written, whit many original and illuminating notations. The historical background the author gives adds a most needed cultural and philosophical perspective on human thinking (and biases) in the exploration of one of the greatest scientific mysteries.

Iris Fry provides an excellent summary of origin of life theories and research. In a somewhat journalistic style she briefly revisits the early "thought leaders" and proceeds to show how orgin of life theory has progressed to the present in keeping with advances in scientific knowledge of molecular chemistry and cell biology. She covers the current schools of thought, supporting research, and major players of the naturalism community without taking sides. This is an excellent resource for someone who seeks a general understanding of the state of origin of life science and its future challenges.