When the Invasion of Land Failed: The Legacy of the Devonian Extinctions (The Critical Moments and Perspectives in Earth History and Paleobiology)

My BA is in biology and I read quite a bit on genetics, cladistics, tectonics, geological eras and evolution. I've recently read books like The Planet of the Bugs (Shaw), the Assent of Birds (Reilly), and the Evolution of Plants (Willis & McElwain) and I decided that, instead of a book that followed a group of animals through their evolution, I wanted a book on the ecology of a specific geological period, so I could see how the different groups interacted. McGhee's Whenthe Invasion of Land Failed:The Legacy of the Devonian Extinctions, was perfect. (I'd previously read McGhee's second book: Carboniferous Giants and Mass Extinction, but this book was even better, and I now wish I'd read the two books in order.)Our understanding of evolution and geological eras has changed significantly in the past 50 years. It's now understood that geological eras and evolution itself reflect not just the passage of time, but the movements of the earth's tectonic plates and periodic extinction events caused by ice ages, volcanism, and comets. Thus, a group of organisms can be doing fine until some major extinction event occurs, get largely wiped out, and have to start over. The group of organisms -- the tetrapods (four legged fish) who were trying to establish themselves on land experienced two major extinction events during the Devonian (between 419- and 358 million years ago) and had to start over, using slightly differnt approaches, until they finally succeeded. As the vertibrate tetrapods struggled, they found themselves in a race with the arthropods (insects) to see who could dominate the land. Meanwhile, during the Devonian, both were committed to eating other animals, or dead plants, since neither had evolved a way to eat living plants. That alone made for a completely different ecology that the one we experience today.Other authors tell a rather linear story of how one group or another evolved. McGhee tells a much more complex story of how the different groups evolved together, each playing their own advantages and disadvantages off against each other. This is a new way to understand the evolution of life that takes advantage of McGhee's ability to integrate lots of new information.Sometimes, in spite of very clear descriptions and definitions, it can all get a bit overwhelming. I read a lot more about the evolution of O2 in the atmosphere than I wanted to, but overall it was interesting and exciting. I assume this text was written for graduate students, but it can certainly be enjoyed by intelligent non-specialists, if you put a little effort into it. I strongly recommend this book for those who want to really understand the evolution of the earth and its living systems.

I rated it 4 stars in that it is very technical for laymen and I had some problems keeping track of the technical language and time periods in the Devonian. However, it is packed with some good facts and it appears when things go wrong they come in series or pulses during some of the extinctions of the Devonian. In my opinion, I think that the Fish Vertebrates would eventually became land dwellers, no matter how many had failed in the attempt, because a lot of fish species seemed to have most of the equipment for evolving into terrestrial animals. It appears that when a winning combination of characteristics evolves in a single species, it radiates into many species. I think this was the case in the some of the Devonian fishes. The land environment was right for habitation with the ozone layer, along with plants and insects already existing on land making ready made niches for the vertebrates to occupy. It's not a case of "IF", but When and Whom. The real question is, which one made onto land and became the ancestor of all existing and extinct Vertebrates? This maybe an unanswerable question, but, don't stop trying, science may find more interesting facts about our terrestrial ancestors in there research. My favorite candidate for the ancestor is Tiktaalik, but that is only my laymen opinion and besides I like Neil Shubin

I enjoyed this immensely. If you appreciate paleontology, evolution and biology you will definitely appreciate this book. I’ve always been fascinated by the Devonian Period and this book gets into a tremendous amount of detail. It’s on par with a college level textbook and well worth the money.

I'm an art school graduate, and do not have a background in science, but this book was a delight to read. The writing is clever, fun, and insightful. I learned so much from this book, I'm actually reading it again.

I have nothing but the greatest respect for the author and the vast, exhaustive work that had clearly gone into the writing of this exceptionally thorough, comprehensive book. But, having said that, for a knowledgeable yet non-professional lover of palaeontology, for me, getting through many parts of this book was like pulling teeth. The language is heavy with scientific terminology to the point where some paragraphs are pretty much unintelligible and the style simply isn't engrossing for someone from the outside.If I were a student and this were a text book and I had the guidance of a professor then no doubt, my experience would have been radically different - but as that was not the case, I would suggest "amateurs" think long and hard before spending their money on this as it is a struggle. Ultimately, I am happy to have completed it but also, relieved.

Requested by my husband for Christmas.

Great, fast, thanks!

Looked like an interesting book, but within a few pages, it was a disappointment. It would appear that the author is trying to popularize information about the two greatest extinction events in natural history, one in which almost all life on land disappeared. There's a lot of new research data there, and that's interesting, but he tends to get bogged down in details only a paleophylogenist could love:"Yet it can be seen in table 3.r that the zosterogrammids and cowiedesmids are more derived chilgonath millipedes...."His favorite word, occurring at least once every few pages is "plesiomorphic."In summary, too detailed for the casual, albeit educated and interested reader, and probably too "popularized" to serve as a review for those in the fields. I have only one doctorate, and it's not in paleontology, alas.

This book describes a wonderful time, the end of the Devonian period, when the world's oceans had monumental reefs of a size far surpassing anything that has been since, with an unmatched richness of marine life. It was in this world that our fish ancestors started coming into land - to be killed. This was one of the five great extinction events, even more dramatic than the end-Cretaceous event: the late Devonian extinction. This event eliminated all the strange animals in the morphological gap between fish and amphibians we see today, and also the different groups of ostracoderms and the placoderm fishes, all but one order of trilobites, graptolites, most Tabulate and Rugose corals and many, many others. This was a tremendous loss of diversity with a dramatic effect on all subsequent evolution of life. No reefs like the Devonian ever formed again. Its is not clear from the fossil record how land was eventually re-settled by 5-digit vertebrates: they don't (yet) appear in the fossil record. The early vertebrate colonists that appear in the fossil record before the end-devonian extinctions (like 7-digit Icthyostega and the earlier 8-digit Acanthostega) did go extinct without leaving any lineage: they are not our ancestors. How much richer would be the world today if still had 7 and 8-digit walking fish and their own "amphibian" and "reptile" descendants? What other possibilities would be open to evolution? We will probably never know.

George R McGhee, the author of this work, has a fluid, readily assimilated writing style that makes it a joy to read. The text is backed up with helpful line drawings plus a section of coloured illustrations. Before dealing with the Devonian extinctions the author takes us through a consideration of the origins of life on earth in fascinating fashion. Life on land in the Devonian period got started twice and then failed before a third attempt brought lasting success. It's a scintillating story every bit as exciting as a mystery thriller with all kinds of outlandish characters involved. If either of the two earlier attempts at land colonisation had succeeded, some animals might well have had more than five toes and five fingers. The way in which early plants established a beachhead on land is equally attention holding.The work includes a preface, eight chapters, notes, references and index. The chapters are: 1: The Evolution of Life on Land. 2: The Plants Establish a Beachhead. 3: The First Animal Invasion. 4: The First Catastrophe and Retreat. 5: The Second Animal Invasion. 6: The Second Catastrophe and Retreat. 7: Victory at Last. 8: The Legacy of the Devonian Extinctions.All told, we have here a top grade example of how to research, develop and compile a scientific work for general readership. There's never a boring moment as you get with quite a number of novels. Better still, the evidence for the existence of the prima face unbelievable is so well presented that it makes you want to jump around singing: 'I'm so pleased! I was so sure it must be like that! And now here's the evidence to show that it surely is. How exciting! What a read!' Yes folks, it really is as good as that.

One for those who wish to delve beyond the perennial fascination with dinosaurs and go in search of a more 'primitive' flora and fauna. It is a masterful examination and distillation of decades of research into the Devonian period written by a professional, rather than a journalist, which can be heavy going at times; I got the impression that this was something written as an undergrad 'textbook'. Nothing wrong with that but the lay reader may find it a little too dry and academic to sustain interest, although the story it tells, how evolution always seems to 'find a way' to fill niches in any environment, is both remarkable and spell-binding. For those brought up on Bakker's infectious prose, this may seem a little dry, almost arid, but it tells a fascinating story about the colonisation of the land by, first the plants, then the 'insects', and finally, after severe setbacks, the tetrapods; the four-footed.

If you wish to learn more about the Devonian an the two main extinctions at that time, this is the book for you. In my opinion more colorful views of the ancient landscape flora and fauna and photos of the fossils are missing.

Der Autor beschreibt detailliert die ersten Tetrapoden, ihre Vorfahren und Umweltbedingungen. Er findet eine gute Balance zwischen trockener, detaillierter anatomischer Bescheibung und der Schilderung der daraus gezogenen Schlussfolgerungen, so dass das Werk definitiv auch für Laien wie mich gut geeignet ist. Der Schreibstil ist durchgehend unterhaltsam.