Thursday, May 12, 2016

The Fifth Miracle




Title: The 5th Miracle – The Search for the Origin and Meaning of Life
Author: Paul Davies
Publisher: Simon & Schuster, 1999 (First)
ISBN: 9780684863092
Pages: 304

Life is the most wonderful phenomenon in the universe. If you reduce its complexity to its most basic elements, it is nothing more than a collection of ordinary material that doesn’t differ at all from inanimate objects. Still, living beings are so fundamentally different and inexplicable that science has not been able to cast its beacon of searching light on the issue of origins of life. About half a century ago, at the instant when DNA’s secrets were coming out, it was widely believed that the puzzle would be solved in a matter of a few years. But decades later, science has not been able to advance knowledge much deeper than where it was. Paul Davies is a physicist, writer, broadcaster and a professor, who has authored many books on popular science. In this book, Davies presents some unusual ideas on the origin of life. Being an advocate of panspermia, he postulates the origin of earthly life taking place on Mars! A presentable case is made out with novel scenarios and clever reasoning. Since the subtitle also mentions a quest to the meaning of life, philosophical enquiry into the nature of life is also included. We know that evolution does not have foresight nor involve a direction to an ultimate goal towards a higher being. Natural selection makes it blind to be oblivious to the advantage of an entire species as compared to the survival benefit of a particular animal. This book is a model case of how a physicist can introduce novel concepts in a conservative field such as biological studies.

Those who first pick this book up from a bookshelf would wonder at the significance of the title. The mystery is neatly explained in the preface, and is linked to the chapter on Genesis in the Bible. God first created the Universe, then made light, then the firmament and the fourth in line was dry land. After arranging the ‘infrastructure’, God commanded that vegetation may appear on land. This first reference to life in the Bible is arranged as fifth in the sequence of miracles, and hence the title ‘The 5th Miracle’ is the most perfect for a book that makes its quest on the origin, nature and meaning of life. The earth is bountiful in life, and there are indications that the presently inhospitable terrain of Mars was once home to life. There may be several variants of life, which may not resemble life as we know it. Davies spells out autonomy, reproduction, metabolism, nutrition, complexity, organization, growth and development as the essential characteristics that delineate life in any form. At the same time, the chain of unification runs through all forms of terrestrial life whether it is a plant, animal or a simple bacterium. For example, take the protein Cytochrome C, which is made of hundreds of amino acids. This protein is present in plants and animals. The copy in humans differs from that of Rhesus monkeys in just one amino acid, out of a total of hundreds. The human cytochrome protein differs from that in wheat by about 45 amino acids, providing solid proof that man diverged from the line of plants pretty early in his development as compared to simian forms. This is also a proof of evolution at work.

Before looking at how life originated, a general discussion on why and if life had to appear on earth. When a physicist writes a book on popular science, we can be pretty certain that a reference to the Second Law of Thermodynamics would somehow be included. According to this now famous theory, the entropy, or level of disorder, in the universe always increases. However life brings about order in complexity and it may appear that biological systems violate the thermodynamic principle. This notion is false and Davies really tries his best to dispel doubts in this regard. The Second Law is applicable only to closed systems in which matter or energy does not enter into the system. However, terrestrial life-forms make an open system, in which the sun’s energy is always available. Even with localized order, the entropy of the universe taken as a whole increases, thus underlining the truth of the law. The author faces an uphill task in explaining how life itself took root. Today’s beings use a genetic code encoded in the DNA to manufacture proteins essential for their survival and reproduction. The author compares this to software of the DNA and hardware of the proteins. However, all attempts to explain the origin of self-replicating molecules end in confusion, as it is not forceful enough to convince skeptics.

Davies makes an extensive survey of organisms existing in specialized niches like deep sea thermal vents and nutrient-deficient habitats. Pyrolobus fumarii is the organism that sets the record for highest temperature at 113 deg C. Introduction to organisms that thrive in extreme conditions is presented with good reason. Spectacular conjectures on the origin of life – biogenesis – follow next. The author is much interested in the concept of panspermia, the theory that places the origin of life somewhere in the deep mists of space, which reached the earth hitchhiking on a comet or meteor. It is also possible that life originated in Mars; where there is abundant proof that running water flowed through the terrain. Martian meteorites have been found on earth, the most recent and fruitful being a piece of rock discovered in Antarctica. Traces of organisms that once lived in Mars have been detected by researchers, though the chain of reasoning is tenuous and highly imaginative. But problems still persist. Even if it is believed that a meteor impact dislodged a piece of rock containing microbes, it has to undergo the tremendous ordeal of radiation in space, heat of entry into earth’s atmosphere and the shock energy of the impact on earth. Since the argument is purely hypothetical, Davies comes up with several mechanisms by which microbes may just be able to survive the bodily transportation to another planet, each being weirder than the previous one.

This book on the origins of life is written by a physicist. We have heard the axiom that ‘physicists defer only to mathematicians, while mathematicians defer only to god’! True to the maxim, most of the authors referred in the book are physicists, thus curtailing the real-life significance of it. Even Fred Hoyle is quoted more times than Charles Darwin. This excessive reference is all the more inappropriate when we remember that Hoyle was a stubborn opponent of the Big Bang theory, while still clinging to his pet hypothesis that the Universe always existed. Also, Hoyle is the co-author of a research paper that ‘found’ that great pandemics visited the earth when our planet travelled through the tail of a comet. Davies expresses rational, even controversial, arguments throughout the book, but some of his remarks seem to be deliberately designed as to be quoted out of context as proof of a creator of the world. For example, “The conclusion has to be that without a trained organic chemist on hand to supervise, nature would be struggling to make RNA from a dilute soup under any plausible pre-biotic condition” (p.131). What about this? Wouldn’t this be the choicest nectar for creationists and proponents of intelligent design? Then again, he states on p.263 that “although biological determinists strongly deny that there is any actual design, or preordained goal, involved in their proposals, the idea that the laws of nature may be slanted towards life, even if not contradicting the letter of Darwinism, certainly offends its spirit”. This book by a non-expert on biological systems lacks proper depth and appeal. This is only recommended to those who want to learn the theories occupying the extremes of probability.

The book is recommended.

Rating: 2 Star

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