Non-Fiction Reviews

The Eerie Silence: Are we alone in the Universe

(2010) Paul Davies, Allen Lane, 20.00, hrdbk, 256 pp, ISBN 978-1-846-14142-3

Houghton Mifflin Harcourt, US$27.00, ISBN 978-0-594-13324-9


Just as one of this popular science book's subtitles suggests, this is in no small part a work that looks at the Fermi paradox. The Fermi Paradox is extremely well known to those concerned with SETI (the Search for Extraterrestrial Intelligence). In case you are not versed in SETI lore, the Fermi paradox was put forward at the time of the World War II Manhattan (atomic bomb) project as a puzzle after dinner by the physicist Enrico Fermi. The paradox is this. Given that it is unlikely that humanity is the only technological civilization in the Galaxy (an assumption), and given that the age of the Galaxy is billions of years old (fact), yet only 100,000 light years across (fact), then even colonising habitable worlds at 0.01% the speed of light an interstellar civilization would traverse the Galaxy in just 100,000,000 years and indeed could do so a few score times since the Galaxy sported habitable worlds. Yet, as we do not see evidence of our Earth having been visited (there are no aliens here on Earth or even fossil spacecraft), it does appear as if the paradox's initial assumption is wrong and that we are indeed in that unlikely position of being the only technological species in the Galaxy! (So, so much for the Copernican principle.)

Note, I said this "book's subtitles" (plural). In Britain the book's subtitle is ' Are we alone in the Universe'. The book's other subtitle for N. America is 'Renewing our search for Alien Intelligence'. And so in addition to addressing Fermi Paradox type questions, the book also is a celebration of 50 years of the SETI project and in particular its hero Frank Drake. Davies himself seems to have great respect for this man (as do I) who has effectively devoted his life to a negative result as we have not detected alien intelligence.

In part the book is an excellent brief review of SETI and a very worthy tribute to Frank Drake, and for this alone I can recommend The Eerie Silence to you. Davies also is good at running through the Drake equation (the key probability factors determining alien intelligence) and distinguishing intelligent technology-wielding life from non-sentient (or should I say non-highly sentient and technology wielding) life. Also he neatly (and I feel rightly) points out that SETI has primarily been a radio frequency search but that this might not be the communication medium favoured by a Galactic civilization. (In fact, I have long thought ever since I was taught quantum physics in the 1970s that another means of communication would be far better than radio, but alas if I am right then we would never, ever be able to accidentally eaves drop.) Davies speculates a number of Fermi Paradox options including that life might be common but intelligent, technology-wielding life so rare that we may be the only example in the Galaxy. Indeed he speculates interestingly that 'science' on Earth may be unique to the Galaxy.

All this is well and good, and such musing makes the Eerie Silence a compelling read for hard SF enthusiasts, scientists into SF and not to mention writers. However here is where the good news ends because Davies spends a fair chunk of the book making biological speculations and it soon becomes clear to life scientist readers that Davies is decidedly no biologist. In fact to put it bluntly his molecular genetics and palaeobiology biology to take just two life science strands sucks. Jack Cohen was surely right in warning that astronomers, or physicists, should not tread into life science without a biologist holding their hand. Davies bless him blunders in completely unaware he is an elephant in a china shop treading without regard all over biological understanding. Now I do not take pleasure in saying this. Indeed I attended Paul Davies' book launch lecture in London that was hosted by the Royal Astronomical Society as part of the Burlington House group of learned societies. At this lecture everyone else seemed to be either an astronomer or a lay member of the public. They lapped up his presentation and to be fair it was interesting (as is much of The Eerie Silence): after all this subject is very SFnal and packed with sensawunda (sense of wonder). Furthermore, Paul Davies' narration is quite capable of capturing an audience and/or readers' attention. Yet surely we are now all old enough to realise that a charismatic messenger, or message, by itself lends no credibility as to a message's validity.

Another fair bit of the book is devoted to speculation as to intelligent life in the Galaxy and where we might look for evidence of it. Many of his ideas would not be out of place in an entertaining discussion at a science fiction convention with SF writers, readers and scientists around the table, and there is nothing at all wrong with that. However his misunderstanding of biology is so great that SF writers who might be tempted to mine The Eerie Silence for ideas should do so with caution if they want their story to be real hard SF founded on sound science. This misunderstanding was so glaringly evident when Davies gave his Burlington House book-launch talk that I dared not raise issues at Q&A, or even quietly in the reception after, lest I be viewed as being overly harsh: sometimes discretion is the better part of valour. Indeed nor do I intend now to go through the book chapter and verse in case it seem I am attacking Davies for reasons other than critical review. However I will give you two examples to illustrate what I mean.

Davies interestingly suggests that aliens may have visited the Earth in the distant past. Of course, this is a very tried and tested science fiction concept and is the sort of thing that makes the book of appeal to SF aficionados: all well and good. He even suggests that they may have left a message for us. This too is very SFnal, which makes such speculation easy (if not fascinating) to digest by science fiction fans. Equally intriguing to many fans would be the notion that the aliens may have left a message in DNA. Alas here, for life scientists (let alone biologists who enjoy SF), there are some problems not least of which is sex. Bluntly, sex jumbles the parents sets of genes and so any message even a comparatively simple one such as Pi to 10 decimal places is unlikely to survive over geological timescales: the aliens would be far better off with a message carved on a slab of igneous rock and placed in an artificial cave on the Moon. Yet, as indicated, sex is just one problem. Bog standard mutation (or even genetic drift) would likely excise any genetic message unless the genetic message itself conferred some Darwinian advantage to the organism carrying it. In short, for a number of reasons (and not just one fundamental one) Davies' notion of a genetic message left for us by an ancient, visiting alien intelligence is really a non-runner for any biologist worth his or her salt.

Second, as a possible explanation for the Fermi Paradox, Davies puts forward the possibility that the very nature of the Galactic environment over geological timescales is hostile to technology-wielding species capable of interstellar travel to arise. This is another interesting notion and there is some merit to it. However Davies goes on to suggest that there is a periodicy in Earth's mass-extinction events that seem to relate to our Solar system's motion in the Galaxy. Now, while this too is an intriguing notion, such regular periodicy in mass extinction events is actually very difficult to see. Importantly, extinction events vary: you cannot just pick and choose such events to obtain your periodicy. For instance CIE (carbon isotope excursion) events largely relate to marine calcareous shelled families of species such forams, whereas large igneous province related extinctions have a terrestrial component to them, and 'iceworld' events are (some of us think) due to key evolution events that in turn are related to carbon processing. (Admittedly others have different theories.) By now some of you may be beginning to see that not only do we have an idea as to the likelihood of principal extinctions but that not all extinctions are alike. Yet if there were something in the Galactic environment 'somehow' periodically affecting life on Earth then those extinctions would be of a type that relates to that 'somehow' (hence only relate to a certain type of extinction and not all extinction events so reducing the chance of finding periodically) but would have to be a preferred explanation (be more likely to be the cause) than the explanations we already have which while not certain are decidedly odds-on bets.

Now this is not to say that Davies may be saying something that in the years to come we find out to be true. However, with each individual biological notion he puts forward (as interesting as it is) there are, after just a little thought, good reasons to dismiss it. Yet because he presents us with so many ideas, by simple weight of numbers I concede that there may be a possibility that one of them turns out to lend some insight into the Fermi Paradox. With respect, this is not good science (or even good popular science) in which a central hypothesis is presented and discussed. Instead it is a blunderbuss approach that might (only 'might') work because a pellet of the many in the buckshot might hit the target.

In short, when Davies strays into the life sciences more often than not he leaves science and enters science fiction territory that is dressed up as science; if you will this is not 'science fiction' but 'fictional science'. For many scientists into SF this is unlikely to be welcome as real scientists like their science as an exploration of fact and their science fiction as explorations in 'fiction'. This is a shame as, as I said, the book does neatly cover some interesting SETI programme ground and contains a sound tribute to Frank Drake. Alas many of the book's biological dimensions really let it down and if this is truly representative of how SETI scientists consider life science implications then this aspect of their discipline is decidedly parlous. The Eerie Silence is of truly uneven quality. This is a shame because the subject matter is beyond doubt fascinating and Davies' imagination fertile. I can easily see some astronomers and astrophysicists uncritically absorbing all Davies has to say. Indeed I lapped up much of his non-biological speculation. However, as we are talking about alien life and life by definition being biological it is impossible to ignore biological science aspects and if we are to include these then surely an effort must be made to build a case on sound biological understanding. Would that Davies had teamed up with a bona fide broad-based and experienced biologist then we might have had a real cracker of a book. Instead we have one that, while undeniably fascinating, is decidedly flawed. A very real shame as I was looking forward to buying into Davies' perspective.

Jonathan Cowie

[Up: Non-Fiction Book Review Index | Science Articles | SF Author: Website Links | Home Page: Concatenation]

[One Page Futures Short Stories | Latest Site Additions | Most Recent Seasonal Science & Science Fiction News]

[Updated: 10.9.15 | Contact | Copyright | Privacy | Editorial | Site Origins/History]