Rare Earth: Why Complex Life is Uncommon in the Universe (Hardcover)

Nearly twenty years ago, James Trefil and Robert Rood published "Are We Alone?". From a list of then-known conditions needed to allow life to begin and evolve, the authors offered optimistic and pessimistic scenarios on whether alien civilizations were likely to exist. Ward and Brownlee have improved the resolution of this question, using the latest information. Sadly, but almost certainly correctly, the come down strongly on the pessimistic side.

Paleontology has come far since Are We Alone? was published. Ward and Brownlee's account surveys utilizes the wealth of recent information derived from research studies done during the past few years. With life beginning over 3 thousand million years ago, their task is formidable. Yet they carry us through the stages life without bogging down in pedantic expression. They show how misleading simple pictures of life's progress can be, showing how even "simple" creatures are astonishingly complex.

The studies and researchers they discuss offer a wealth of new information, including a few acute surprises. Evolution is fraught with disaster scenarios. Ward and Brownlee offer a good discussion of these, particularly the great Permian dying. Diversity loss from this extinction was severe. Was it the result of a reduction in available DNA patterns due to the loss of species? This is a new question for which the authors call for further research in its response.

The most innovative chapter in the book deals with the impact of plate tectonics on evolution. More than simply the drifting of continental land masses, the authors describe how severely mobile continents impact ocean currents, air masses and climate generally. Little considered by paleontologists except as a dating and location device, Ward and Brownlee make continental drift a major factor in evolution. Since no other planet in the solar system exhibits tectonic activity, what is the likelihood this phenomenon occurs on planets circling distant stars? No tectonics, no stimulus to higher life forms and interplanetary communication.

In short, this book covers an immense amount of territory in explaining how life starts and likely continues under the proper conditions. They present nicely balanced explanations and critiques of recent research findings. Even outlandish ideas are given a patient hearing. As they remind us, who would have thought life could dwell at the bottom of the ocean's depths? It's well worth investing in this view of life's history. While posing many questions, the authors show how innovative thinking may someday provide answers . Anyone considering entering a scientific field will discover countless areas of investigation. This book should find a place on your shelves for current knowledge and future reference. Perhaps you might gain a place in a revised edition. [stephen a. haines - Ottawa, Canada]

I found this book's description and analysis of the evolution of life quite fascinating. Even if you do not agree with the authors' conclusions, this history of evolution is worth the time taken to read the book. I must add, though, that while the title states affirmatively that complex life is uncommon, the authors are careful to explain that their analysis is based on data provided by only one planet and solar system, and that complex life might prove to be more common than they suggest.

Overall this is a great book, and a fascinating read. I recommend it wholeheartedly.