In the Blink of an Eye: How Vision Kick-started the Big Bang of Evolution (英語) ペーパーバック – 2004/9/6
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Between 543 and 538 million years ago, something remarkable happened. After hundreds of millions of years of gradual and painstaking evolution, suddenly the process exploded into life. For the first time animals evolved hard external parts. For the first time there was evidence of active predation, with both hunters and hunted rapidly developing both armaments and defences. And in this short space of time -- the blink of an eye, in geological terms -- the number of different classifications of animals, or phyla, mushroomed from three to thirty-eight, the number we still have today. The 'when' and the 'what' of this extraordinary event, known as the 'Cambrian Explosion', have been known for some years and were made famous in Stephen Jay Gould's bestselling book WONDERFUL LIFE. What has until now been speculation is the 'why'. Andrew Parker's astounding explanation, which is becoming increasingly influential and accepted, is fully explored and described in this groundbreaking book. A scientific detective story which encompasses disciplines as diverse as biology, history, geology and art, IN THE BLINK OF AN EYE is destined to become a popular-science classic.
Parker's book is sub-titled The Cause of the Most Dramatic Event in the History of Life. The 'event' referred to is the so-called Cambrian Explosion - the point at which 'all the major animal groups evolved hard parts and became distinct shapes'. How and why did this happen? The author is a specialist in the field, and his research has led him to formulate a version of the 'Light Switch' theory in answer to this big question. But he's also a good synthesizer and explainer of all the relevant history, background and theory. The book ranges across - and connects up - a variety of scientific disciplines, theories and fields of research in a highly readable and intriguing fashion --このテキストは、絶版本またはこのタイトルには設定されていない版型に関連付けられています。商品の説明をすべて表示する
Definitely worth a read. It, however, brought up a bunch of other questions that I now want answers too.
To begin with, the author looks at what life is very probably to have been like during the Dark Ages of the Precambrian. Professor Parker approaches the subject by suggesting that internal and external body plans have had different evolutionary histories and rates, and that the basics of internal body plan-those aspects that are not preserved well if at all in the fossil record-had already arisen during that early period of life's existence. Those changes in structure that would require the greatest effort and the most time, were so firmly set by the end of the period that while some phyla have dropped out, no new ones have been created. Focusing on the newer interpretations of the Ediacaran and Burgess life forms, the author believes that most of the external body plans were worm-like because there were few forces for the development of others. While the internal structures were distinct to accommodate different niches, the externals remained unchanged.
Everyone agrees that the efflorescence of external forms, particularly those with hard parts, after the Cambrian was both prolific and amazing. For Darwin, who had no access to information on Precambrian life or genetics, it posed a major challenge to his theory of evolution. It appeared as if life came diverse and fully formed out of nowhere and began to proliferate exponentially from its first appearance. What everyone hasn't agreed on heretofore is the reason for that sudden burgeoning of body forms.
Professor Parker takes the reader through various arguments that illustrate his thesis, namely that prior to the Cambrian it was essentially a blind world. He suggests that prior to that point in time light could be sensed, but visual images were not possible, that neither the "hardware" nor the "software" for actual vision existed. Without that sense predation, while it existed, was almost accidental. Once the creation and interpretation of images was possible, vision drove the evolution of both predator and prey in an escalating manner.
Superb reconstruction of an unusual time in life's history.
There are actually well founded theories that explain why life diversified suddenly 543 millions years ago. No need of supranatural being for that.
Now is it the final answer for that mistery? I doubt it but it is up to you to decide.
I am a student of perception and I wanted to be persuaded by Parker's argument, but the book itself is not well done. There is a ridiculous attempt to generate suspense about the conclusion Parker ultimately draws...a conclusion that is basically no surprise if you read the dust jacket. The language is often stilted and pedantic, to my eye, making me wonder if this isn't a warmed-over dissertation recast as pop science.
The most irritating element of the book, however, is the routine citation of items from the research literature...but with no reference list to which to turn for the full citation. Even decent popular science books have at least a few sources for further reading, and notes of some sort for the particulars of research cited. Parker's book has neither.
The book has some value (hence the three stars) for pointing out a variety of interesting elements of invertebrate visual system evolution, but does not help at all if one wants to follow up such threads.
Okay, I'm not a paleontologist and not a biologist, so maybe I'm talking through my hat. Simon Conway Morris, however, IS an eminent paleontologist. If you want a truly informed review of Parker's book, see Morris's review in American Scientist, July/Aug 2003, p. 365 ff. Quoting very briefly: "The jaunty style becomes increasingly irritating, and the claims for scientific originality increasingly questionable."