What's This All About?

The common ancestor to all life on Earth did not originate on Earth. Instead, it arrived on the early Earth from space. Indeed, it may have not appeared spontaneously anywhere in the universe but may, instead, be the product of deliberate design. If so, evidence for this may exist in the genome sequence of one or more organisms. Complete genome sequences for several organisms have now been determined and numerous others are being prepared in laboratories around the world, so the data in which such evidence may be found are present or will soon come to hand. The first message from an intelligent extraterrestrial civilisation may not emerge from a radio telescope but, instead, from a DNA sequencing machine. Such a message may, in fact, be present now in every cell in your body.

Now, you're perfectly within your rights to dismiss this as a far-fetched speculation not even worthy of an X Files plot, no less serious scientific investigation. But consider that Francis Crick, who won the Nobel Prize for his discovery, with James Watson, of the structure of DNA--the very molecule in which the genome is encoded, believes the most probable explanation of the origin of life on Earth is that all present-day life is descended from bacteria deliberately spread through the universe by intelligent extraterrestrials.

Now, Crick is certainly in the minority in holding this opinion; most origin of life researchers believe the common ancestor of present-day life was spontaneously assembled from non-biological molecules on the early Earth. But neither is Crick's theory of "Directed Panspermia" dismissed as the ravings of a lunatic--most surveys of theories of the origin of life rank it among plausible scenarios which evidence to date cannot exclude.

Almost thirty years ago, after a lecture by Crick at Harvard which presented his theory, Matthew Meselson observed that Crick's supposed extraterrestrials would have almost certainly included a message in the genome of the organism with which they were seeding the universe, intended to be read when the distant descendents of that organism evolved into beings intelligent enough to read the blueprint for their own construction--the genome coded in their DNA. At the time, nobody imagined that before the turn of the century humans would, indeed, figure out how to read DNA, begin to amass a library of complete sequences for a variety of organisms, and be well along the way to sequencing their own three billion letter genome.

We have the phenomenal luck to be living in the era when, for the first time in human history, data are being decoded from living organisms which might just contain evidence in favour of Crick's theory. Discovery of a message in the genome of one or more organisms would be, arguably, the most significant scientific discovery since Copernicus. It would drastically alter how humans perceive our place in the universe, and it would, once and for all, show us that not only are we not alone in the universe, but that we owe our very existence to the benevolent actions of beings who lived before the Sun was born.

However prestigious Francis Crick's reputation may be, and however seriously his theory may be taken, the idea of looking for a message from extraterrestrials in the DNA of this or that organism may seem like the craziest science-fictional notion. In fact, in 1989, I wrote a science fiction story myself, We'll Return, After This Message, about precisely such a search. Now less than decade after I wrote the story, and in the very year and month in which it is set, I'm making available the tools which permit you to search for such messages yourself.

To effectively search for messages in genomes, you'll need to understand a little about how DNA works, how it can be used to store arbitrary information just like a CD-ROM, how it's possible to send a message that's comprehensible to beings who share no common language and what such a message might resemble, and how it can be decoded.

With that information at hand, you'll be able to understand how to use our Java-based interactive genome browser to search for messages in the actual genomes of real organisms whose sequences have been determined to date. As additional organisms are sequenced, the library of genomes you can search will expand. For practice, you can search the genome of a plausible but fictitious organism in which a variety of messages have been encoded.

At the end of many of the documents, you'll find links to others logically related to them. You're free to explore all the various documents and resources in this area in any order you wish by starting from the master table of contents, a link to which appears at the end of every document, and which you can also reach by clicking the logo at the top and bottom of every page.

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