"Do you feel lucky? Well do ya?" asked Dirty Harry. Paleontologist Peter Ward and astronomer Donald Brownlee think all of us should feel lucky. Their rare Earth hypothesis predicts that while simple, microbial life will be very widespread in the universe, complex animal or plant life will be extremely rare. Ward and Brownlee admit that "It is very difficult to do statistics with an N of 1. But in our defense, we have staked out a position rarely articulated but increasingly accepted by many astrobiologists."Their new science
Is the field of biology ratcheted up to encompass not just life on Earth but also life beyond Earth. It forces us to reconsider the life of our planet as but a single example of how life might work, rather than as the only example.
The revolution in astrobiology during the 1990s was twofold. First, scientists grew to appreciate how incredibly robust microbial life can be, found in the superheated water of deep-sea vents, pools of acid, or even within the crust of the Earth itself. The chance of finding such simple life on other bodies in our solar system has never seemed more realistic. But second, scientists have begun to appreciate how many unusual factors have cooperated to make Earth a congenial home for animal life: Jupiter's stable orbit, the presence of the Moon, plate tectonics, just the right amount of water, the right position in the right sort of galaxy. Ward and Brownlee make a convincing if depressing case for their hypothesis, undermining the principle of mediocrity (or, "Earth isn't all that special") that has ruled astronomy since Copernicus. --Mary Ellen Curtin --This text refers to an out of print or unavailable edition of this title.
Rare Earth by Peter Ward Costumer Review
This is one of the most wide-ranging and readable of all science books aimed at a non-specialist audience. The authors raise Big Questions in astronomy, planetary evolution, geology, climatology, ecology, and biological evolution, reminding us of how interdisciplinary the extraterrestrial life debate really is. The vast array of subjects they address could make this book an ideal discussion text for a course designed to introduce non-scientists to scientific issues and methods. The book, at least in its hardback edition, has an uncrowded format that makes it easy to read.
Ward and Brownlee accumulate a lengthy series of arguments in support of their position that, while simple life may be relatively common, complex life is rare. At first glance, these arguments seem persuasive. However, a closer reading reveals that the authors sometimes tilt the debate in their favor by choosing the argument that best supports their case even when the evidence is very limited or ambiguous, e.g. their statement that plate tectonics "may be vanishingly rare in the Universe as a whole." How can they know this when our sample is limited to our own solar system? Sometimes, the authors make unsupported blanket generalizations, e.g. "On every planet, sooner or later, a planetary catastrophe can be expected that either seriously threatens the existence of animal life or wipes it out altogether." Stating that "it just seems to have been by chance that our Jupiter formed as it did" is hardly scientific. Oddly, after stating that SETI is a futile effort if their hypothesis is correct, the authors go on to say that "There probably are other civilizations in the galaxy that have radio telescopes." In the end, the fundamental limitation to such arguments is that they are based on the only biosphere we know -- our own. This is summed up in the authors' statement that "It appears that Earth got it just right." Life as we know it may not exhaust all the possibilities.
There are some errors. Venus does not always present the same face to the Sun. Nicholas Copernicus was Polish, not Danish. Frank Drake's equation was developed for a meeting held in 1961. One hopes that the authors will clean up these details for a second edition.
This review is from: Rare Earth: Why Complex Life is Uncommon in the Universe (Hardcover)
4.0 out of 5 stars Stimulating and educational, but beware the fine print, January 21, 2002
By M. A Michaud "michael_michaud" (Dulles, VA United States)Sharing is BLESSING
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