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Museums: Darwins life and work on exhibit
Books: Deciphering the Grand Canyon
"Victory for evolution in Dover," Geotimes, February 2006
AMNH Darwin Web site
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Grand Canyon: Evidence, Theories, and Mystery
by Wayne Ranney.
Grand Canyon Association, 2005.
ISBN 0 9382 1682 1.
Canyon: Solving Earth’s Grandest Puzzle
by James Lawrence Powell.
Pi Press, 2005.
ISBN 0 1314 7989 X.
The Grand Canyon was carved by the Colorado River. That statement
is perhaps the only one about the Grand Canyon on which most geologists who
study the feature can agree with certainty.
The details behind that statement remain murky, despite a century and a half of scientific work on the canyon and its evolution. Two new books about the Grand Canyon and its history both human and scientific make clear the complexity and inscrutability of this stunning geologic feature.
Both books, Carving Grand Canyon: Evidence, Theories, and Mystery and Grand Canyon: Solving Earths Grandest Puzzle, were published in 2005, several years after a landmark conference took place in 2000 at the national park. Before the meeting, geologists had yet to hammer out a unifying theory of what ultimately formed the Grand Canyon, and the number of hypotheses had multiplied to several tens of possible scenarios: among them, a very old canyon (80 million years), a very young one (6 million years or less), or a river that once flowed in the opposite direction.
But at the end of the conference, writes Wayne Ranney in his book, Carving Grand Canyon, geologists could settle on that most simple statement, of the river having carved the canyon, as ultimately the only reason for the existence of the feature. Ranney, a river guide and geologist who teaches at Yavapai College in Sedona, Ariz., writes that he is well accustomed to describing this grandest of geological puzzles for laypeople visiting the Grand Canyon, as well as for his students, and his book, published by the Grand Canyon Association, bears that out.
For a first-time visit to the Grand Canyon, this relatively slim volume will come in handy both before and after the trip. The illustrations are useful and straightforward, as is the prose if only sometimes in need of copy-editing and the cover flaps of the book contain a timeline of and elemental data on the river and canyon. Ranney covers the history of the scientists both past and modern and what they thought made the Grand Canyon, building up to an excellent concluding chapter. In the end, he manages to fit the history of the canyon onto two short pages at the end of the 150-page book.
Not so for James Lawrence Powells lengthy tome, Grand Canyon: Solving Earths Grandest Puzzle. Powell, a former geology professor at Oberlin College and now executive director of the National Physical Science Consortium, has turned his fieldwork and writing skills to a twisting and turning tale of the high-walled valley, which is sometimes more confusing and backtracking than the rivers own path.
Powell attempts to tell Grand Canyon history and geology in the context of the life and science of John Wesley Powell (who is no relation to the author). The first half of this book is a paean to Powell, the one-armed, self-educated major who eventually headed the U.S. Geological Survey. While the historic figure is obviously worthy of the focus of a book on the canyon, the repeated use of self-educated, rudimentary formal education and other such descriptive phrases to describe Powell weigh down the storytelling in some places.
Despite this and some other style issues, the author includes some juicy tidbits beyond just the elder Powells adventures and political missteps. He lays out possibly all of the original hypotheses put forth by the earliest scientists to try to solve the puzzle, from the first white man to see the canyon, to the multitude of great men who wrote about it in the early 1900s, and some of the people who continue to explore it today. Powell lovingly describes their lives, the history of biblical versus natural historic thought and of course the Grand Canyon itself.
Solving Earths Grandest Puzzle also contains a few attention-grabbing stories of more modern interpretations of the valleys and rivers deposits. And in the end, Powell attempts to boil down the work done at that geology powwow in 2000 into a chapter, to find a new theory of the formation of the Grand Canyon. His conclusion, however, is more geologically complex, resting more on the uplift of the Colorado plateau as the progenitor of the Grand Canyon than on the simple statement that the river that flows through it carved it. Although parts of the book are very accessible, some of the geology may prove to be difficult reading for a nongeoscientist. Those readers who are geologists, and particularly those who are obsessed with the Grand Canyon, most likely will enjoy this book.
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