Alien message 'may be in our DNA'?
The coded message would only be discovered once the human race had the technology to read and understand it.
Writing in New Scientist magazine, Davies said the idea should be considered seriously.
For more than 40 years astronomers have been sweeping the skies with radio telescopes hoping to catch a signal from an alien civilisation.
So far the search has been in vain. But Davies believes it is wrong to assume that extraterrestrials who may be hundreds of millions of years ahead of us technologically will have chosen to communicate by radio.
Leaving artefacts for humans to find once they are sufficiently evolved -- like the obelisk in the movie 2001: A Space Odyssey -- might be a more attractive strategy, he said.
But ensuring the survival of such an artefact over possibly millions of years would be difficult.
A better solution would be to incorporate information into the human genome, allowing it to be copied and maintained over immense periods of time.One way to do this might be to deliver alien viruses which could infect cells with message-laden DNA, said Davies.
Scientists have recently discovered large sequences of "junk" DNA that contain no genes and appears to be very stable.
"If ET has put a message into terrestrial organisms, this is surely where to look," said Davies.
A computer could be used to find obvious attention-grabbing patterns within these stretches of DNA, he said. If a sequence of junk units of DNA were displayed as an array of pixels on a screen and produced a simple image "the presumption of tampering would be inescapable".
The DNA code was easily big enough to contain a decent-sized novel or a potted history of the rise and fall of an alien civilisation.
Davies added: "Trying to second-guess alien communication strategies is fraught with uncertainty, so we should try everything we can afford. The truth may be out there somewhere. Or it could be a lot closer to home."
Paul Davies, Arizona State University is an associate member of the Australian Centre for Astrobiology at the UNSW
I know this is probably not so new to others who have been here longer being as this is info from 2004 but I found it intriguing.
The question being how many of us believe this to be possible?