Customer Reviews

Life Everywhere: The New Science Of Astrobiology

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David Darling's excellent new book does an effective job of presenting the main topics of astrobiology in a conversational writing style that is easy to read and understand. Without assuming prior knowledge on the part of the reader it clearly explains the very latest research with fascinating details and well-chosen examples that will hold the interest of experts as well as newcomers.
Life Everywhere explores the conditions assumed to exist on prebiotic Earth and the various explanations for how life arose. Supporters of the various hypotheses are lumped together as "surface, sunlight" guys (who believe in Darwin's "warm little pond") and "deep, dark" guys (who believe that life arose near hydrothermal vents). Each new discovery gives a new advantage to one team or the other. The book also discusses the possibility of life on other planets and moons in our solar system, and it gives the most convincing and clear explanation I've found for the possible role of comets in the origin of life's building materials.
The science in Life Everywhere is solid, and the treatment of opposing theories is open and even-handed, with the exception of the Rare Earth theory which, according to Dr. Darling, is a theory based more on theological conservatism than on scientific fact. Life Everywhere is not a large book, but it contains a wealth of up-to-date information about the new science of astrobiology. If you are interested in the scientific study of life's beginnings and limits and the search for life on other worlds, I strongly recommend Life Everywhere as the first book to read for anyone new to the subject. For anyone already familiar with the basics of astrobiology, this is still an interesting new look at a rapidly-evolving science.

The dust jacket quotes Lynn Margulis who suggests a question mark for the title. Cautioned by the question mark, this book is an excellent introduction to astrobiology. Having reviewed Rare Earth by Ward et al., and being unaware of the surrounding debate behind the book, I recommend this rejoinder as highly useful dialectic to put the full context of the argument in perspective, in fact Amazon is selling the two books together. The book also contains some interesting considerations on the issues of divergence and convergence in evolution, and might have been more explicit in suggesting or discussing the issue of the 'inevitability' of life beyond the question of natural selection.

This is the best book on the subject I've come across. It certainly lives up to the billing given by James Kasting, of Penn State Astrobiology Center, on the cover: "A lucid and surprisingly accurate introduction to the field of astrobiology and a thoughtful response to the Rare Earth hypothesis." Chapter 6 pretty well demolishes Rare Earth and exposes its surprising creationist roots. Elsewhere, Darling explains when and where we might expect to find extraterrestrial life, what methods we'll use to detect it, the missions and projects planned over the next 10-20 years, the latest on the controversies surrounding Mars, the Martian meteorites, Europa, organic matter in space, and extrasolar planets, and the principles that might govern life wherever it appears. He manages to cram a huge amount of information and ideas into a small space and yet it's so well explained you never get lost in the detail. It's hard to believe that the "reader" who gave the book only two stars actually read it at all. I can see how it might not be popular with those who want to cling to the belief that the Earth and humans are somehow special. But the fact is this is first-class science in a first-class package.

How can David Darling's wonderful new book "Life Everywhere" appeal to both beginners who know nothing about astrobiology and seasoned veterans who have already read many books about extraterrestrial life? The key is a massive amount of fresh, up-to-date material coupled with superb organization, an exceptionally clear writing style, and the lavish use of anecdotes and examples that make otherwise difficult material fun and understandable. Get a headache thinking about planets or moons in orbit? Visualize a spinning dinner plate with a helping of mashed potatoes in the center and a used stick of chewing gum at the rim! Among other things, David explains how rather than narrowing the search for the origin of life astrobiologists keep finding interesting new ways that life may begin. He describes the formidable survival skills of such lifeforms as "Conan the Bacterium," and he explains emerging technology that will allow us to identify Earth-like planets in other solar systems and then monitor chemical processes would be highly suggestive of life. I particularly enjoyed his sure-to-be controversial analysis of the "Rare Earth" Hypothesis", and his chance discovery of how pre-Copernican thinking may influence science today. Finding Jupiter-sized planets and mashing-up Martian meteorites are important and worthwhile scientific activites, but if you think that astrobiology is little more than this, read David Darling's "Life Everywhere" and think again!

Two things have happened in recent years to persuade most scientists that life beyond earth is not just possible, but likely. Indeed some people, including myself, believe there is, as the title of David Darling's book has it, "Life Everywhere."

Well, not in the center of the sun or on the surface of a neutron star--at least not life as we know it.

"Life as we know it." This is an important phrase that comes up again and again in discussions about astrobiology. "Life as we know it" means life with a carbon base and liquid water. David Darling considers silicone-based life and even life forms so bizarre that we wouldn't recognize them if we saw them, but basically he sticks with life as we know it in this very interesting answer to those who think that life in the universe is rare.

The two things:

(1) The discovery of extremophiles, bacteria that live in sulfurous hot springs, deep inside the earth, and at the bottom of deep oceans. Instead of deriving their energy from the sun, they are able to use heat coming from within the earth to metabolize.

(2) The discovery of scores of planets (albeit not earth-sized planets--yet) revolving around other stars.

What the first discovery means is that life doesn't have to exist or begin in conditions such as there are or have been on the surface of the earth, but can thrive in places previous thought hostile to life. That opens up a whole lot of the universe to life including parts of our solar system previously thought inimical to life, such as in an ocean under the icy crust of Europa or beneath the inhospitable surface of Mars. And the fact that planets are now clearly plentiful means that there are numerous places for life to develop.

Darling, who is an unusually lucid writer and a man who gets to the bottom of things, begins with the nitty-gritty problem of just how to define life. If you haven't been introduced to this strangely knotty problem, this book may open your eyes. Do we consider reproduction, metabolism, growth, etc. in our definition? And which of these elements are essential and which are not? The postmodern definition now preferred by most people I have read is "undergoes Darwinian evolution." Is that adequate? Is that the essence? Darling puts all the cards on the table and lets you decide.

Next Darling recapitulates ideas about how life began. The main new idea is that life may be an inevitable consequence of the nature of matter and energy. It appears that matter is self-organizing. Darling reviews the ideas of how lifeless matter might replicate and how cells might develop from various molecules and water. These "leaky membranes" could be the precursors of the first biological cells. (p. 40)

He goes on to make the case for a universe with abundant life. But along the way he presents a blistering critique of Rare Earth: Why Complex Life Is Uncommon in the Universe (2000) by Peter D. Ward and Donald Brownlee, in which it is argued that the circumstances that allow life are rare and that those circumstances as seen on earth are unlikely to be replicated anywhere else. Darling not only utterly destroys their argument, point by point, but even shows that part of the reason that it was advanced was because they were under the influence of one Guillermo Gonzalez, professor of astronomy at the University of Washington, who is also a creationist with the usual supernatural agenda.

This was bombshell to me. But Darling shows that nearly every argument that Gonzalez makes is designed (pun intended) to discredit the idea that there is life anywhere but on earth. On page 112, Darling refers to an article entitled "Live Here or Nowhere" co-authored by Gonzalez for a publication called "Connections" published by Reasons to Believe, Inc. of Pasadena, California, whose mission is "to communicate the uniquely factual basis for belief in the Bible." The article concludes, "The fact that the sun's location is fine-tuned to permit the possibility of life--and even more precisely fine-tuned to keep the location fixed in that unique spot where life is possible--powerfully suggests divine design."

A couple more points:

First, Darling argues that life forms on other worlds, however dissimilar their chemistry, are likely to be familiar to us in the sense that if there is an atmosphere, some will have wings, and if there is an ocean, some with have fins, if there is a solid ground to walk upon, some will walk and run, and if there is light to see, some with have eyes. This idea of "convergence" is dictated by the laws of physics which requires evolutionary adaptations to take forms that work efficiently within certain environments. Of course if the life forms we eventually discover exist in great dust clouds, their adaptations may be very dissimilar and surprising. Even on solid ground here on earth some run and some hop, some crawl and some slither.

Second, since it is now known that bacteria spores can exist more or less indefinitely (some have been revitalized after hundreds of millions of years of dormancy: see page 150), the once discredited idea of panspermia, namely that life originated elsewhere in the universe and arrived here as spores, has been rejuvenated. Personally, I've always liked this idea championed by Fred Hoyle and Chandra Wickramasinghe; however this book has convinced me that life could arrive from without or develop from within. Either way (or both) seem likely to me.

This book is actually in the form of a long essay defending the hypothesis that life, at least in microbial form, is widespread in the Galaxy.

The author starts by trying to define life. Is it replication? Evolution? Metabolism? Next, he discusses the question of the atmosphere of the early Earth. A reducing atmosphere might produce complex organic molecules in some warm little pond. But the Earth is unlikely to have had such an atmosphere then. That leads to the question of where life originated. Near ocean vents, or on (or just under) the ocean floor? And when life originated. Over 4 billion years ago? When the Earth was still being bombarded by bolides?

The author then discusses meteorites, along with the possibilities for them having brought organic molecules (or even life) to Earth. After that, there's some material on extrasolar planets, including "hot Jupiters," which may migrate right through a stellar system, wiping out all the rest of the planets in it.

A very interesting section is Darling's critique of Ward and Brownlee's book, "Rare Earth." That book contains the view that although microbial life is probably widespread on other worlds, multicellular life (and especially intelligent life) will prove to be rare. Actually, that view, while a minority one, is unremarkable. After all, there is good evidence that unicellular life originated rather quickly on Earth while multicellular life took quite a bit longer. But Ward and Brownlee go further than that, claiming that several things about Earth are special and unusual: the Moon, the exact spacing between catastrophic events, being in the right part of the "habitable zone," having Jupiter to shield it from heavier bolide bombardment, having a high metallicity Sun, having plate tectonics, and being in the right part of the Galaxy! Darling presents interesting rebuttals to these points. And he finishes the chapter by pointing out that a collaborator of Ward and Brownlee, Guillermo Gonzalez, keeps finding signs that the Earth is unique. Darling asks if Gonzalez is letting his religious beliefs influence his scientific views (Gonzalez says that his views that life's origin involved the personal involvement of a supernatural creator have motivated his science and vice-versa). Um, that is a good question. Still, I wonder if that's altogether fair. Ought we ask about Simon Conway Morris, whose religious beliefs support his views on convergence? Or about, say, Fred Hoyle, with his views on panspermia? Or about Freeman Dyson, whose scientific ideas seem rather independent of his religious views? Or about, um, me?

In any case, Darling continues with the debate between Stephen Jay Gould and Simon Conway Morris. Gould argues for divergionism, and says that were we to "replay the tape of life," the odds are that the chordate worm that first incorporated what became the human body plan would have been lost and there would have been no humans. Conway Morris argues for convergionism, and says that no matter what specific species survive, niches tend to get filled. And that means that some creatures very much like humans would have evolved had we replayed that tape. Darling agrees, and adds that even intelligence appears to be convergent.

The author then tells about upcoming space missions to look for life in the solar system and to discover more about extrasolar planets.

Darling concludes that life is a universal phenomenon, life's most important characteristic is to engage in Darwinian evolution, life originates on planets and moons, planets are very common, the evolution of life involves contingency and convergence, and life can be both planet-wide and refugial. But he says that future events may get us to change our minds on some of this. What if we find life on Mars? Or find definitive evidence that Mars has always been sterile? Or find life (or even find complex life) on Europa? What if we spot an atmosphere on an extrasolar planet that suggests life abounds there? What if we find bacteria in interstellar space? What if we find life based on silicon instead of carbon? Or make contact with extraterrestrial artificial life? And while it might be tough to verify it, what if we were to discover that there is no other intelligent life (or no other life) in the universe?

While it wouldn't surprise too many people, the author says it would also be significant were we to verify the existence of a very deep, hot biosphere such as the one Thomas Gold has proposed.

This book is easy to read and informative. I recommend it.

Astrobiology is one of the most exciting and fast-developing sciences in our time, and David Darling's Life Everywhere is a must-read, bang-up-to-date introduction to it. There's real meat in the treatment: this is no lightweight, gee-whiz overview. In fact, compared with other works on the subject, this is very much a "second generation" astrobiology book. It goes beyond pure speculation about whether there's life out there and the weirder forms it may take, to looking more scientifically at what a truly universal biology might be like. Darling explains, for example, that there are good reasons to suspect cells may be a general feature of life and that multicellularity and even intelligence may be convergent properties. He goes into depth about the Martian "fossils" and ocean-on-Europa controversies, and provides one of the clearest treatments of habitable zones to appear in print. Darling paints an optimistic future for this young science. However, the book isn't about *his* theories or opinions but those of the astrobiological community at large. The "Oh please" reader obviously didn't have the benefit of the book when he wrote his review. One of the points Darling makes is that the "goal posts" may have to move as we start to collect biological data beyond the Earth. That's what science is all about: making adjustments and refining our ideas - or throwing them out altogether if necessary - as new information becomes available. The alternative is to be stuck with some dogmatic viewpoint that closes your mind to the possibility of other living worlds.

I would definitely recommend to buy and read this book, but beware... this book is very thought provocing! I have had a Christian (Catholic) education and although I have always been very interested in exact sciences, I never read a book before that challenges you to reconsider so fundamentally the origin of life. I bought this book from Amazon.com ZShops and even now, 6 weeks later, it is not yet completely finished because I needed time after every chapter to let sink down the information.

This book very clearly explains what astrobiology is about and gives you lots of ideas to think about.
One minor point : the writing style is not always very fluent.
Overall a really good book and a must have !

I welcome other people that want to discuss the content of this book with me : send me an e-mail !

While there are many accessible books on SETI, surprisingly few have been written on astrobiology. This is undoubtedly one of the best and most current. The material is so fresh that many of the references are to work published in 2000 and even the early part of 2001. In little more than 200 pages, Darling covers almost every major aspect of the subject and provides a balanced treatment of issues such as the SNC meteorites, extrasolar planets, and the importance to life's origins of exogenous organic matter. He also addresses areas of astrobiology, including panspermia, that were once considered far-fetched but are now beginning to enter the mainstream. I noted only one significant omission. Darling's discussion of life's origins is excellent but focusses almost entirely on "hardware" - the source of the chemicals of life; we are left to wonder about the source of biological information or "software". Otherwise, this is really a very good, very lucid book indeed. But, oh dear! It seems that one individual has been submitting a number of tawdry reviews under various pseudonyms ("Adolf", etc) in an ill-concealed attempt to discredit the author and his work. I'm glad to see that most of these have been removed. But how sad that this very effective forum is marred by silly people with alternative agendas.

Finally a book by a writer that doesn't shirk from answering the hard questions, like is there life out there and if so what would it be like?...I find this new and exciting area of science as area where the greatest leaps in our understanding of the universe will take place. Remember what seems maverick today is tomorrow's norm.