Aquagenesis: The Origin and Evolution of Life in the Sea

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Summary: Explains The Origin and Evolution of Life in the Sea
Review: More lucid science writing from Ellis (Imaging Atlantis, 1998, etc.), who this time cuts a broad swath through the history of marine animals. "This book is about animals whose ancestors came out of the sea and whose descendants returned to it," writes the author. That and a whole lot more, for while almost every aspect of paleontology is rife with ambiguous, speculative, and contentious theories-and Ellis gives many of them sufficient air time in these pages, such as changes in genetic structure to lines of descent-there is no contesting the complexity of the fossil record. And the glory of species complexity is on full display here. From the earliest creatures of the vents, the breeding grounds created by the spreading of the seafloor and strong candidates for the deep-ocean location of the origins of life, to Elaine Morgan's evidence pointing toward an (at least semi-) aquatic ancestor of humans-and she isn't talking about jawless fish, but rather an aquatic ape-Ellis covers an incredible land- and waterscape. There's a rogue's gallery of toothy, spiny creatures (sharks with teeth all over their heads, others big enough and happy to eat a horse) and an equally long list of sideshow marvels, including the wonderful hagfish, which "can emit gallons of nauseating, toxic slime." The theories tendered for the evolution of these creatures are often as fabulous as the creatures themselves: Certainly the descent of whales from giant wolves falls into that category, but less sensational are the beard-pulling contests between academics, such as the Gould/Conway Morris feud. Then there are all the questions that remain unanswered, far more than those with answers, beginning with: How did it all start? Ellis samples from all these topics with the enthusiasm of a child let loose in a candy shop. As entertaining as a three-ring circus, and as scholarly as any intellectually curious lay reader would wish for.