Vertebrate Life (7th Edition)

Book Description

Widely praised for its comprehensive coverage and exceptionally clear writing style, this best-selling exploration of vertebrate life is the only accurate and up-to-date treatment of vertebrates that employs a phylogenetic perspective and focuses on how vertebrates work, integrating ecology, behavior, anatomy, and physiology in an evolutionary context. A new chapter on conservation draws together information about the basic biology of vertebrates and shows how it is essential for biological and regulatory decisions that affect the survival of species. Discussions of anatomy, physiology, and behavior are placed in an evolutionary context, showing readers how animals work and how they got to be the way they are. Contains information about conservation and endangered species status—related to the basic biology of the groups stresses the importance of good biological information for management and legislation. Features a Cladistic perspective which reflects the widespread adoption of phylogenetic systematics (cladistics) as the basis for determining the evolutionary relationships of organisms. Includes emphasis on conservation—Includes the application of basic biological information about organisms in programs of captive husbandry and management of threatened and endangered species. For professionals in the fields of Vertebrate Zoology, Vertebrate Biology Function, as well as Paleontology and Herpetology.

Customer Reviews:

Enthusiastically recommended as a college-level text........1999-03-13

Vertebrate Life would serve as an excellent upper-level college textbook to anyone interested in becoming informed about vertebrates. Professionally, I am a physicist, who after visiting the American Museum of Natural History's Hall of Vertebrates, wanted to learn more about the subject. Even after reading Vertebrate Life, I don't think that I could point out the squamate bone on a fossilized skull. On the other hand, with 733 pages, it is unfair to critize this book about a lack of coverage! The authors provide several pages of excellent references at the end of each chapter. So, if I really wanted to be able to identify a squamate bone, I'm sure that I could have found out from one of references. However, I was troubled by a number of typos, some of the them serious. Figure 15-3 appears to have the second half of the figure repeated as the first half. It would have been nice to see missing illustrations. Figure 3-6b identifies the Otic capsule as "Optic capsule" at one point. This confused me for a while. Even with all this, I was fascinated by what I read, and read the entire book, cover to cover, all 733 pages worth. For the serious student of our natural world, I would recommend spending full price for this book, and plan on spending more than a few hours with it.

Wonderful Life: The Burgess Shale and the Nature of History

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Not Good
LIFE 101
Revolution in thinking about evolution
Elegant prose, science made accessible
Gould's take on the creatures of the Burgess Shale.

Wonderful Life: The Burgess Shale and the Nature of History
Stephen Jay Gould
Manufacturer: W. W. Norton
ProductGroup: Book
Binding: Paperback

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ASIN: 039330700X

Amazon.com

The Burgess Shale of British Columbia "is the most precious and important of all fossil localities," writes Stephen Jay Gould. These 600-million-year-old rocks preserve the soft parts of a collection of animals unlike any other. Just how unlike is the subject of Gould's book.

Gould describes how the Burgess Shale fauna was discovered, reassembled, and analyzed in detail so clear that the reader actually gets some feeling for what paleobiologists do, in the field and in the lab. The many line drawings are unusually beautiful, and now can be compared to a wonderful collection of photographs in Fossils of the Burgess Shale by Derek Briggs, one of Gould's students.

Burgess Shale animals have been called a "paleontological Rorschach test," and not every geologist by any means agrees with Gould's thesis that they represent a "road not taken" in the history of life. Simon Conway Morris, one of the subjects of Wonderful Life, has expressed his disagreement in Crucible of Creation. Wonderful Life was published in 1989, and there has been an explosion of scientific interest in the pre-Cambrian and Cambrian periods, with radical new ideas fighting for dominance. But even though many scientists disagree with Gould about the radical oddity of the Burgess Shale animals, his argument that the history of life is profoundly contingent--as in the movie It's a Wonderful Life, from which this book takes its title--has become more accepted, in theories such as Ward and Brownlee's Rare Earth hypothesis. And Gould's loving, detailed exposition of the labor it took to understand the Burgess Shale remains one of the best explanations of scientific work around. --Mary Ellen Curtin

Book Description

"Gould has brought to light one of the least known but most spectacular paleontological discoveries of all time….a brilliant tapestry."—Martin Gardner

The Burgess Shale is a small limestone quarry formed 530 million years ago. In it are the remains of an ancient sea that nurtured more varieties of life than can be found in all of our modern oceans. Stephen Jay Gould explores what the Burgess Shale reveals about evolution and the nature of history. 116 illustrations.

Customer Reviews:

Not Good.......2007-07-15

This book is quoted so often in the literature that I thought I was going to read something profound. It isn't. Conway Morris and others were right to criticize it. Not sure what all the fuss is about. As a well reasoned argument Gould missed the mark.

LIFE 101.......2007-03-19

I READ THIS BOOK WHEN CAME OUT YEARS AGO. NOW YOU CAN GET IT AT AMAZON AS A BARGAIN BOOK. THIS WONDERFUL STORY TELLS ABOUT AN ALTERNATE EARTH THAT NEVER MADE IT. SOMETHING DESTROYED IT UTTERLY. AND WONDERFUL LIFE FOUGHT BACK AND WITH TIME BECAME GIANT ANIMALS ROAMING THE LANDS OF THE EARTH. THE K-T EVENT. WACKED AGAIN! BUT LIFE ENDURED AND BECAME US...

READING THIS BEATS WATCHING THE FLUFF ON SATELLITE AND CABLE. AND IT MAKES YOU THINK. IT HELPS YOU PUT TWO AND TWO TOGETHER TO ARRIVE AT YOU!

Revolution in thinking about evolution.......2007-02-25

Burgess Shale is the most important find ever of remains of early animal life on earth. Stephen Jay Gould explains why, and also why it took almost seventy years before the true significance of this treasure trove began to dawn upon the scientific world. In Gould's view, the 1970's reappraisal of the Burgess Shale fossils represents no less than a Copernical revolution in thinking about the way life on earth has evolved. While this may be, or may not be the case, the tale of how this reappraisal came about is thrillingly and competently told.

As a complete layman in the field of paleontology, I found the insets, explaining the basics and the terminology of the science very helpful. The beautiful drawings by Marianne Collins also helped me a lot to get a feel of what the amazing creatures of Burgess Shale must have been like while living.

The tale of how three British paleontologists, through their work on the fossils, arrived, much to their own surprise, upon conclusions very different from Walcott's (who first discovered Burgess Shale) is a captivating one. Gould's analysis of why Walcott in his time could not possibly have seen his find in it's true light, is something I could have done without.

But then, even if this part holds less interest for me than the main story, were it not for social obligations, I would have finished this book in one sitting!

Heartily recommended for all interested in the history of life on earth.

Elegant prose, science made accessible.......2007-01-10

I feel remiss for not writing a lengthy review of the book, but I hardly have time to do it justice as I go about my work. Instead, I will summarize the major points.

Gould is an exceptional writer who makes science accesible for all readers. I know that this book has drawn new paleontologists into the field, and it definitely encouraged me. It also inspired research programs, numerous books by detractors (e.g., Conway-Morris's "The Crucible of Creation"), which are unfortunately not nearly as well written, and helped popularize the importance of the Cambrian explosion and the lack of understanding of this crucially important time in the history of life. While some of Gould's ideas have since been proved wrong (e.g., he felt that there were more body plans, phyla, represented by Burgess Shale animals than at present but these animals have since been seen to fit into existing phyla), other ideas (e.g., that nearly all phyla arose in the same geological instant) have stood the test of time.

As with all science, the book should be approached critically. Unfortunately, there are few scientists who are able or willing to make their work accessible to the lay person so that all can have an opportunity to understand, enjoy, and contemplate.

Gould's take on the creatures of the Burgess Shale........2006-01-31

Stephen Jay Gould (1941-2002) was a very popular (and controversial) scientist/professor. He wrote several books and many articles in Natural Science magazine. In Wonderful Life, he focuses on the Pre-Cambrian fossils of the Burgess Shale in western Canada.

In doing so, he creates a book with three divisions: the biography of Charles Dolittle Walcott, a description of the creatures from that find, and his own interpretation of what they mean in evolutionary theory.

I found the narrative about Walcott interesting as he was surely a man of powerful intellect, standards and drive. But Gould does go out of his way to not just point out that Walcott never performed a serious study of the fossils, but to explain ~why~ and why his early analysis was wrong.

There is a one-hundred-plus section in which each of the specimens is described in great detail. He uses this as a means to discuss the advances in techniques and approaches to studying these fossils, how our understanding of them changed over time, replacing Walcott's ideas. The discussion of scientific approach was fine, but frankly, I was a bit overloaded with the detailed descriptions of the Burgess creatures. A set of good drawings would have gone a long way - a picture being worth a thousand words and what. This section became tedious to read.

The third section, Gould's interpretation of the data, is also a bit confusing and has turned out to be controversial and even wrong. Gould presents his thoughts on the diversity of life in the Cambrian vs modern times, and why there is such a difference. Simon Conway Morris, one of the young scientists he lauds, would later criticize him in his own book about the Burgess Shale fossils, The Crucible Of Creation (1998).

When published, Wonderful Life was a best seller and won awards. I am honestly not sure why. While it is fairly interesting, it is not a 5-star book.

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The American Horseshoe Crab

Manufacturer: Harvard University Press
ProductGroup: Book
Binding: Hardcover

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ASIN: 0674011597

Book Description

The American horseshoe crab that comes ashore on the East Coast in vast numbers to mate and nest is much the same creature that haunted the coast before the time of the dinosaurs. It is among the world's most intensely studied marine invertebrates, critical to our understanding of many groups of organisms, both modern and extinct, and crucial to the ecology of large estuaries such as the Delaware Bay. Some stocks of this great survivor, whose ancestors made it through the mass extinction some 286 million years ago, have been severely depleted today because of overfishing and habitat destruction.

Carl N. Shuster, Jr., H. Jane Brockmann, and Robert B. Barlow are at the forefront of research on Limulus polyphemus, and in this book they bring together twenty scientists who have worked on all aspects of horseshoe crab biology to compile the first fully detailed, comprehensive view of the species. An indispensable resource, the volume describes the horseshoe crab's behavior, natural history, and ecology; its anatomy, physiology, distribution, development, and life cycle; the puzzle of its immune system; and its present management and future conservation.

Ammonites and the Other Cephalopods of the Pierre Seaway: Identification Guide (Fossils & Dinosaurs)

Average customer rating:

Excellent, well written and documented, and informative.

Ammonites and the Other Cephalopods of the Pierre Seaway: Identification Guide (Fossils & Dinosaurs)
Neil L. Larson , Steven D. Jorgensen , R. A. Farrar , and Peter L. Larson
Manufacturer: Geoscience Press
ProductGroup: Book
Binding: Paperback

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ASIN: 0945005253

Customer Reviews:

Excellent, well written and documented, and informative........1999-09-12

This book was written by the folks at Black Hills Institute of Geologic Research. Neal is the leading authority of invertibrates of this period. The book lists species and where specimens have been found. I have found it to be an excellent desk reference as well as a great field guide. Recommended reading for the Ammonite hunter.

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Palaeobiology of the Invertebrates
Paul Tasch
Manufacturer: John Wiley & Sons Inc
ProductGroup: Book
Binding: Hardcover

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ASIN: 0471052728

Invertebrate Palaeontology and Evolution

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A Comprehensive Treatment of a Fascinating Field of Study
Power of Paleontology

Invertebrate Palaeontology and Evolution
E.N.K. Clarkson
Manufacturer: Kluwer Academic Publishers
ProductGroup: Book
Binding: Paperback

ASIN: 0045600082

Customer Reviews:

A Comprehensive Treatment of a Fascinating Field of Study.......2007-05-05

Dr. Clarkson presents a detailed and informative summary of all major aspects of invertebrate evolution. The book is organized in a step-wise fashion that introduces the reader to the main principles of the field of paleontology (including genetics, populations and micro- and macroevolution) and then moves into detailed descriptions of the various invertebrate phyla. Be aware that this is not your typical coffee table book; rather, it is written at a level best appreciated by those with a biological background or by introductory students in this field. Descriptions are appropriately detailed and concise and are accompanied by a wealth of similarly detailed drawings and images. I particularly enjoyed his chapters on molluscs, echinoderms and crinoids. It is a valuable accompaniment to other books that have been written on the Burgess Shale and early forms of non-vertebrate life. Both the armchair paleontologist and the professional will find this to be a most valuable addition to his or her collection of books on this wonderfully diverse group of ancient animals.

Power of Paleontology.......2002-06-22

This very fine invertebrate paleontology textbook strikes a nice balance between focus on the paleobiology/taxonomy of the organisms and theoretical topics in the science. The well-crafted illustrations help to make the sometimes intricate details of fossil morphology clear. Clarkson has a knack for bringing forth key details that illuminate ancient organisms (e.g., the hysteresis mechanisms that control the liquid in cephalopod chambers), and he writes with a wry sense of humor (see the Lehmann quotation on p. 245). The importance of convergent evolution is apparent throughout the book, and is one of the main lessons to be learned from the science of invertebrate paleontology. The next edition of this book needs to stop calling the Ediacarans a "fauna" (the term "biota" is preferable, as we are not sure that Ediacarans were indeed animals). I also have quibbles with the higher taxonomy presented in this book for other groups. Overall, however, this is an outstanding presentation of invertebrate paleontology.

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Fossil Crinoids
Wow - if you ever wanted to know about crinoids ...

Fossil Crinoids
Hans Hess , William I. Ausich , Carlton E. Brett , and Michael J. Simms
Manufacturer: Cambridge University Press
ProductGroup: Book
Binding: Hardcover

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ASIN: 0521450241

Book Description

Crinoids have graced the oceans for more than 500 million years. Among the most attractive fossils, crinoids had a key role in the ecology of marine communities through much of the fossil record, and their remains are prominent rock forming constituents of many limestones. This is the first comprehensive volume to bring together their form and function, classification, evolutionary history, occurrence, preservation and ecology. The main part of the book is devoted to assemblages of intact fossil crinoids, which are described in their geological setting in twenty-three chapters ranging from the Ordovician to the Tertiary. The final chapter deals with living sea lilies and feather stars. The volume is exquisitely illustrated with abundant photographs and line drawings of crinoids from sites around the world. This authoritative account recreates a fascinating picture of fossil crinoids for paleontologists, geologists, evolutionary and marine biologists, ecologists and amateur fossil collectors.

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Customer Reviews:

Fossil Crinoids.......2004-08-07

"Fossil Crinoids" written by Hans Hess, William I. Ausich, Carlton E. Brett, and Michael J. Simms is a wonderfully appointed book all about crinoids from 500 million years age and a last chapter on todays crinoids.

"Fossil Crinoinds" is a very good text for the casual collector of fossils and for the paleontologist with paleoecology and paleozoology stongly associated. "Fossil Crinoids" is divided into two sections. The first, is a general part with Crinoid form and function, with systematics, phylogeny and evolutionary history, then fossil occurences, taphonomy or the process behind the preservation of all fossils especially soft-bodied remains, and ecology and ecological interations. The second part and main part of the text deals with assemblages of intact fossil crinoids, which are described in their geological settings, ranging from the Ordovician to the Tertary, from all around the world. These deposits are mostly here in the United States and Canada, but some are from Europe. The one I was particualrly interested are the ones from Crawfordsville, Indiana which is not too far away as the crow flies from where I'm at.

Crinoids have been found in limestone deposits around the world and they date back to 500 million years ago. If they were like their distant cousins of today, they were brightly colored feather like appearence likened to those found on the coral reefs of today. Crinoids had a key role in in the ecology of the ocean communities. Everything you want to know and more that you'd like to know about crinoids is here in this book making it a wonderful reference book.

"Fossil Crinoids" gets a solid 5 star rating for a very well put together reference text making for ease of understanding of the subject matter.

Wow - if you ever wanted to know about crinoids ..........2000-12-30

I recently bought a plate of fossil crinoids and wanted to identify them. This book has been helpful but not perfect for the task. What the book did do is allow me to come to a radically deeper understanding of what I was looking at (which is what I really wanted). Great diagrams and photos! Magnificent clear explanation! If you have any interest in these funny little animals buy this book.

Index fossils of North America: A new work based on the complete revision and reillustration of Grabau and Shimer's "North American index fossils",

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Index fossils of North America: A new work based on the complete revision and reillustration of Grabau and Shimer's "North American index fossils",
Hervey Woodburn Shimer
Manufacturer: M.I.T. Press
ProductGroup: Book
Binding: Unknown Binding

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Fossil Invertebrates
Paul D. Taylor , and David N. Lewis
Manufacturer: Harvard University Press
ProductGroup: Book
Binding: Hardcover

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ASIN: 0674019725

Book Description

Fossil Invertebrates introduces readers to the biosphere as it was hundreds of millions of years ago, when seas teemed with animal forms both familiar and strange: ammonites and corals, mollusks and sponges, crinoids and trilobites. On land, terrestrial forms were beginning to make their mark, leaving behind traces such as burrows and track ways and other fossil evidence of the important transition to life on land. The plates in this book capture the incredibly detailed impressions and casts of ancient life, contrasting them with forms, such as the horseshoe crab and the chambered nautilus, that persist today virtually unchanged.

The shells and hard exoskeletons of invertebrates make them excellent candidates for fossilization, and the amateur fossil collectors are more likely to uncover an invertebrate fossil than any other kind. The fossilized remains of invertebrates dominate university collections and museum holdings worldwide and their study continues to yield important insights into the nature of evolutionary change and the impact of climate change on biodiversity, as great explosions of diversity were succeeded by mass extinctions. Paul D. Taylor and David N. Lewis, both of the Natural History Museum, London, have written a comprehensive and accessible resource, one that provides undergraduates and amateur fossil enthusiasts with a means to understand and interpret this rich fossil record.

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Enjoyable & informative, but with multiple flaws
Great ideas but too many digressions
Fascinating content, terrible writing
The eyes have it
A great read but where is the bibliography?

In the Blink of an Eye
Andrew Parker
Manufacturer: Perseus Publishing
ProductGroup: Book
Binding: Hardcover

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ASIN: 0738206075
Release Date: 2003-04-15

Book Description

An accomplished young scientist solves one of the greatest mysteries of evolution: What caused the dramatic explosion of life half a billion years ago?

The Cambrian Explosion is universally referred to as biology's "Big Bang." About 550 million years ago, there was literally an explosion of life forms, as all the major animal groups suddenly and dramatically appeared. Why did it happen this way? Why didn't these creatures continue the slow, plodding pace of evolution, appearing only very gradually in the fossil record? Although several books have been written about this surprising event, none have explained why it occurred. Indeed, none were able to.

Here, for the first time, Oxford zoologist Andrew Parker reveals his theory of this great flourishing of life. Parker's "Light Switch Theory" holds that it was the development of vision in primitive animals that caused the explosion. Precambrian creatures were unable to see, making it impossible to find friend or foe. With the evolution of the eye, the size, shape, color, and behavior of animals was suddenly revealed for the first time. Once the lights were "turned on," all animals had to either adapt or die, and in a geological instant, the world became a very different place. A controversial theory but one that is quickly gaining ground, the Light Switch Theory promises to revolutionize our understanding of life and light. Drawing on evidence not just from biology but also from geology, physics, chemistry, history, and art, In the Blink of an Eye is the fascinating story of a young scientist's intellectual journey, and a celebration of the scientific method.

Customer Reviews:

Enjoyable & informative, but with multiple flaws.......2007-10-01

Other reviewers have mentioned Andrew Parker's proclivity in 'In the Blink of an Eye' to digress, to present his thesis as more revolutionary & unique than it actually is, & to fall into a 'gee whiz' style from time to time, & I will merely second those critiques, while agreeing with previous reviewers that Parker's book is nevertheless an entertaining & surprisingly broadly informative read.

But my primary criticism of Parker's book is his failure to construct a solid logical argument for his thesis, which is that the evolution of vision was THE cause of the Cambrian Explosion ('CE'). Parker tends to zigzag through his chapters, & upon reaching the end, claim that he has formulated a logically-sequenced argument, which he rarely has.

Few paleontologists, I think, would disagree with the idea that the development of vision (as distinct from mere light sensitivity) gave an enormous acceleration to Early Cambrian evolutionary rates, but Parker wants more than mere primum inter pares for vision, he wants it to have sole credit for the Explosion. To quote one reviewer: "What happened in the explosion is that animals acquired armor, hard body parts, and a huge variety of different shapes. Parker explains that the shapes and armor came along because eyes came along."

Yes, that's precisely Parker's explanation, but his argument leaves a skeptical reader not entirely convinced. At one point, Parker states (paraphrasing) that one must separate the CE itself (i.e., the evolution of fossilizable hard parts made of calcite) from the Cause of the CE. Stating it doesn't necessarily make it so. Sometimes an events IS the same thing as its cause.

Parker spends considerable time making the case that trilobites were the first creatures to develop vision. By Parker's own, slightly buried, report, this first lens that made vision possible was a calcite lens. I.e., it was either literally or virtually a modified bit of calcite body armor. If a bit of modified armor came first & made vision possible, how can one claim that "...armor came along because eyes came along."?

I don't want to argue that the evolution of vision wasn't crucial, merely that it's more reasonable to view it as 'primum inter pares', 'first among equals'. There's just too many evolutions of 'firsts' happening in the CE: first calcite secretion by multiple phyla, first eyes with considerable degrees of vision in multiple phyla, and several new body plans. It's probably more realistic to view these all as giving important positive feedback to each other, instead of crediting one as being the sole source of all the changes.

On this account, I think Parker's book would have been improved by a consideration of how & why so many different phyla evolved both calcite body coverings & vision so nearly simultaneously. The problem, to the best of my knowledge, is that we're still pretty much stumped by this one. Perhaps it's a useful place in earth history to postulate the incorporation, by several phyla, of bacterial DNA coded for calcite secretion, a la Lynn Margulis.

It makes no sense to somehow imply that the evolution of vision by trilobites somehow produces the evolution of vision in trilobite prey species. Evolution doesn't work that way, though that's the impression Parker just sorta leaves hanging out there.

Parker, like Dawkins before him, cites Nilson & Pelger's theoretical calculations of the rapidity--in geological time terms--with which "eyespots" can evolve into camera-type eyes. Perhaps a fruitful field for Parker to consider than would have been why then did vision not evolve prior to the CE? 99+% of all animal lenses through geologic history have been made of organic materials rather than calcite. Why then did lenses not evolve in multicellular life prior to the evolution of calcite secretion & hence the first calcite lens?

But again, the final line here is that Parker's book is an enjoyable & worthwhile read, even if it ultimately fails to marshall a complete & compelling argument in support of its thesis.

Great ideas but too many digressions.......2007-07-31

In the blink of an eye splits the Cambrian Explosion into two pieces, the development of multicellular life (the "precambrian surge", which is mostly just dropped) and the evolution of "hard parts" as a result of the development of vision (which is the bulk of the book). The story does not flow well because of the frequent digressions, but there is a lot of support for his main conclusion. He mentions that the end of "snowball earth" comes a littel too soon before the Cambrian Explosion. At the same time he makes the point that 38 phyla were developed during this time and none since. I think evolving 38 phyla would take some time. I also think the snowball earth did not just go away quietly, it may have been several million years before the precambrian animals were able to dispurse across the seas to the point that they were detectible and primed for the explosion. The book is very up-to-date and worth reading, but ber prepared to listne ot too much autobiography and "and then I did..."

Fascinating content, terrible writing.......2006-04-23

The content of this book is simply fascinating. Not only does it present a plausible solution to the Cambrian enigma, it also provides a huge amount of information on the role of color and eyesight in nature. The only drawback is that the writing style is extremely clumsy and sometimes the logic is very difficult to follow. The author should have teamed up with a professional writer.

The eyes have it.......2006-03-09

What triggered the Cambrian Explosion?

Starting around 543 million years ago, there was a 10-million year period (give or take 5 million years) in which the number of phyla on this planet went from three to thirty-eight. After that, no new phyla appeared. Something dramatic happened during that time period, but why? There was also a major evolution of external body parts in all phyla at that time, but what caused all this?

There are some explanations that have been taken seriously for the Cambrian explosion, and Parker reviews a number of them. The first is that the Cambrian was just a great time for rapid evolution. But there is evidence from embryos of nonskeletised animals that indicates that the Cambrian was probably not a particularly hospitable time after all. The second group of explanations that Parker deals with attempt to cover not only the Cambrian explosion itself, but the Precambrian changes in internal body plans. But Parker wants to know what caused the explosion itself, and feels strongly that the Precambrian changes are not an integral part of this. The third explanation is that the physical environment changed significantly at the start of the Cambrian. That means changes in, say, oxygen, carbon dioxide, or phosphorus levels. But these levels changed at plenty of times, and the start of the Cambrian doesn't appear to be all that special. A fourth explanation is that shallow-water continental shelf areas increased at the start of the Cambrian. A fifth is that there was a "Snowball Earth" that ended just prior to the Cambrian. A sixth is that collagen was acquired by animals during the Cambrian. A seventh deals with the generation of new niches: perhaps the increased availability of free-swimming plants could create a new niche. An eighth deals not with niches, but with all feeding modes. And yes, one or more of these explanations may be pretty close. But they don't satisfy Parker, and he has an explanation that makes plenty of sense, namely that around 543 million years ago, there was a sudden development of sight among animals. That means eyes, and brains to interpret the light that reaches those eyes. By the way, one of the early species to acquire eyes may have been the box jellyfish, which has no brain! But the trilobites are the creatures that Parker dwells on: they originated at the start of the Cambrian, and they appear to have had eyes (and brains) at that time.

The book covers plenty about what eyes are, what different sorts of eyes there are, how eyes evolved, and what eyes are used for. As an example, rabbits have eyes on each side of their heads. A reason is that they spend plenty of energy to avoid getting eaten. That means they want as close to 360-degree vision as they can get, since they intend to run away at top speed towards safety if they see a predator (and keep running for their lives if the predator chases them). That is a cost-effective idea! On the other hand, foxes spend more of their energy chasing potential food. They don't need 360-degree vision for this, so they have eyes in front, where they can be used to provide depth perception. That lets them judge the distances to possible prey and saves them from costly futile chases.

It doesn't take much imagination to, um, see that the introduction of vision could lead to a huge evolutionary explosion, as species developed armor, camouflage, and more defenses against suddenly non-blind predators. So this is indeed an interesting hypothesis.

A critical issue is just how long it would take for working eyes to evolve from simple patches of light-sensitive cells (sandwiched between a transparent protective layer and a layer of dark pigment). But as the author explains, a paper by Dan-Eric Nilsson and Susanne Pelger shows that a few hundred thousand years should be ample time to accomplish all this. Vision could indeed have arisen in an evolutionary blink of an eye. And that may well have led to the Cambrian explosion.

At the end of the book, Parker considers possible triggers for the evolution of eyes, such as increases in the available light reaching the Earth's surface. I think these areas are worth pursuing as well.

I thoroughly enjoyed this book, and I recommend it.

A great read but where is the bibliography?.......2006-02-07

Parker presents a very plausible theory that seems to explain the great increase of species in the Cambrian explosion. In fact, it is so well-presented (much like Darwin included overwhelming arguments and examples in Origin of Species) that you are tempted to repeat Huxley and say that it is so obvious, why didn't I think of that?

Like other reviewers, I cannot comprehend the absence of a bibliography. With one, I would have rated the book 5 stars.

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