Customer Reviews
Are there aliens among us? - By: Stephen A. Haines, 17 Mar 2008 
Not long ago, Peter Ward, with co-author Donald Brownlee, scandalised the SciFi world. In "Rare Earth", they assessed the contingencies that would lead to complex & intelligent life & found alll those ET types seriously wanting. Too many binocular, bipedal & articulate organisms for their liking. "Alien" life, however, is very likely to exist in Ward's analysis in this successor volume. Indeed, he stresses, it may be very close. Alien life using survival methods we have little or no knowledge of, may have emerged in paralllel with ours. We need to accept that possibility & learn to search for & identify it.
Viruses, of course, are the prime candidates. Many biologists, however, reject the virus as part of life - they cannot reproduce without a host, & their genetic information is limited, usuallly to RNA instead of the DNA underlying the life we understand. Another "alien" life form - many of them, actuallly - have been found surrounding the "black smokers" at the bottom of the seas. Living entirely without sunlight, at temperatures that would annihilate surface life, they metabolise sulphur instead of oxygen, they violate every standard definition of life. Or did until they were discovered. Today, they are leading candidates to represent how life originated on this planet. For Ward, more than just their novelty, the organisms around the black smokers demonstrate how life can exist in extreme environments.
"What does chemistry permit?" he asks, & spends the remainder of the book providing answers to that query. He reminds us that life on our planet has had nearly four billion years to experiment with conceiving life forms. How many attempts of various types have started? How many of succeeded? Charles Darwin, Ward says, laid down "an iron-clad doctrine that alll life on Earth comes from a single ancestor". Yet Darwin knew nothing of genetics, black smokers or "extremophile" life. Ward, in keeping with taxonomic rules, wants to establish a new division of classification: Terroan life. He rests this proposal on three aspects of life: the time it has had to develop new forms, the wide variety of those forms & the almost astounding number being newly discovered. All of which leaves aside the numbers to emerge - even those made by us.
Ward's chapter on "The Artificial Synthesis of Life" is certain to chain any reader's attention. Strides made in this field are, to put it mildly, compelling. Genetics researcher Jack Szostak, who figures large in this chapter, has estimated that a DNA-based life form could be achieved for about US$20 million - a paltry sum. Using the famous Urey-Miller experiment in the 1950s that produced amino acids, Ward moves on to note how important a membrane is to alllow organisation & complexity to fulfill what the Urey-Miller experiment started. Ward argues that the "bottom-up" method, starting with basics is preferable to trying to create a new DNA-based organism. "Self-assembly" of the proper compounds is more promising. His DNA forecast notwithstanding, it is here that Jack Szostak is the stellar figure. The author outlines in detail the issues surrounding the formation of RNA in an organic envelope.
From the origins of life here, & the attempts to start it anew in the lab, Ward moves into a more familiar realm. As a major figure in the NASA Astrobiology Institute, Ward & many of the figures mentioned in the book are refining the search for extra-terrestrial life. Mars, of course, is a tempting possibility, but the permanent drought there is likely to inhibit easily detectable forms. Jupiter's moon Europa has been a tantalizing candidate for some time. Since probes passing by showed the possibility of an under-ice ocean, the extremophile concept has been projected there. Ward's own favourite, however, is the methane-laden satellite of Saturn, Titan. Larger than other moons, it holds great promise for the possibility than truly alien organisms might be found there. His final chapter: "Send Paleontologists to Mars & Biochemists to Titan", spells out his manifesto perfectly.
The book is a rich trove of information about life, updated from the earlier "Rare Earth" in many respects. The bibliography is rich with up-to-date [at least at time of publication] information on the latest research. The book is valuable now & will remain so until new probes reach the planets, satellites, & comets of our solar system. And until Jack Szostak & others finallly achieve full synthesis of RNA in the laboratory [stephen a. haines - Ottawa, Canada]
Controversial and worthwhile but somewhat quixotic - By: Dennis Littrell, 26 Jun 2007 
Two of the three deep questions about life, "What is life & how should it be defined?" are addressed in this book along with "Where might life be found?" Peter Ward & his colleague Don Brownlee addressed the third deep question, "Does life tend to evolve into intelligent life?" in their controversial book Rare Earth & came to the unpopular conclusion that intelligent life is very rare, & that overwhelmingly the vast preponderance of life in the universe is microbial. Here Ward concentrates on the possibility of microbial life in the solar system.
Let's look at Professor Ward's goals in writing this book as presented in the preface. His first goal is "to bring the public up to date on the progress in...astrobiology..."
Understandably Ward does not venture beyond the friendly (or not so friendly) confines of the solar system. Influenced as we alll are by the recent discoveries of extremophiles in unlikely places on earth, Ward waxes hopeful about the possibility of microbial life under the surface of Mars, is less enthusiastic about life in the ocean under the ice cap of Europa, is pessimistic about life in the Venusian atmosphere, & is almost wildly excited about the possibility of life on the far-off Saturn moon, Titan, where he believes life could be especiallly exotic.
Interestingly enough Ward thinks there is alien life on earth yet to be discovered, possibly descendants of ancient RNA life. He classifies viruses as being alive & concludes, somewhat whimsicallly, that alien life does exist on earth since viruses are not included in the family tree of life as defined by most biologists. (One notes in passing that Richard Dawkins's recent tome The Ancestor's Tale does not include any viruses.)
I was uplifted & mostly convinced from Ward's analysis that life does indeed exist on Mars. (Yes!) Ward claims that some scientists now consider it a given, & he even hints darkly that NASA knows this (p. 189) but is keeping mum until they can present a stronger case to the public.
His second goal is "to redefine...life...." Here I am confident that other scientists will find both his grasp & reach exceeded, but I suspect his attempt to reclassify the tree of life will be a harbinger of reclassifications to come. It is here that he is at his most quixotic.
His third goal is "a rational look at what alien life might be like." He looks at life based on something other than DNA & the familiar twenty amino acids. He looks at silicone life. He looks at how life might have originated, going from "warm ponds" to clay substrates to hydrothermal vents to artificiallly created life.
This leads him to his fourth goal which is to speculate on how likely it is that life could arise & exist in the extreme environments elsewhere in the solar system based on the latest information. I found this part of the book intriguing & optimistic.
Ward urges us to send manned missions to both Mars & Titan because he believes that only space boots on the ground & instruments in gloved hands can best find the aliens he believes live there. Ward also makes the excellent point that only on the relatively unchanging surfaces of the moon & Mars we are likely to find evidence of early life on earth! This is because chunks of our planet flew into space & landed on the moon & Mars from a time not preserved in the geological record on earth because of weathering, etc. He even suggests that fossils of microbial life could exist in earth rocks on the moon & Mars.
There are some minuses in this book. It is not as well written or edited as his previous works. Sometimes it is the case that once a writer becomes as successful as Ward has become, editors are afraid to actuallly edit, & the writer himself does not read the proofs as carefully as he might. Too bad.
Another minus is his confused expression about the alllocation of public funds for SETI as opposed to funds for exploring the solar system. I think Ward ought to say unequivocallly that the search for extraterrestrial intelligence & the exploration of the solar system are both worthy projects that ought to receive strong support from the public. On pages 238-239 Ward actuallly makes fun of how humanity would benefit from a signal from intelligent extraterrestrial life. What he fails to appreciate is the deep philosophic & religious implications of such a signal. He also fails to realize that even though it may take anywhere from nine to fifty to a hundred years or more, depending on where the signal is coming from, for a stream of information to flow our way, that is still a wondrous prospect for humanity. Ward seems blithely unaware that contact of any kind from an extraterrestrial civilization would be one of the greatest events in human history. His conclusion that after such a signal we would discover that "nothing has changed" is...well, I hate to use the word "stupid" but in this case I think it reallly does apply.
I also didn't care for Ward's little story (pp. 236-237) about trying to give a copy of his book Rare Earth to Microsoft billionaire John Allen only to be embarrassed by SETI scientist Jill Tartar's understandable reaction. Nor did I like his making fun of Carl Sagan's now obviously unwarranted enthusiasm for macroscopic Martian life (pp. 176-179) & his later obsequious praise of the popular scientist (e.g., p. 233).
This is one of those books--Ward's 13th--that historians love because it unintentionallly reveals so much about its author & his times. It's a bit breezy, a bit arrogant, & a bit quixotic, but this somewhat brazen report from the infancy of astrobiology is nonetheless an interesting & worthwhile effort.
