Humans love to hunt for the hidden. It intrigues us. We love to solve puzzles, search for clues, work a thing out from scraps of information. Other species have these investigative tendencies, usually as a desire to find food or a mate, but humans seemingly take it to abstraction and do it for recreation and the joy of knowledge. But nothing exists without function in the natural world, so perhaps it is a spin-off of our hunting, social and self-preservation instincts. Cue anthropologists.
Science shows us things we cannot see from a superficial examination and of reveals to us things we did not anticipate. It is exciting and surprising. It also shows us that things have a basic coherence and work by the same set of fundamental rules. That is useful, but can also be surprising.
I was reading in Nature yesterday how old spy satellite images, combined with modern spectrographic techniques and digital imaging can detect evidence of ancient human civilisations hidden in the ground. Humans have a distinct ‘signature’ called an ‘anthrosol’ that shows up old settlements no longer visible on the ground. Humans produce distinctive traces in the soil from building matrials and organic waste, or scat, if you want a hunting term. We cannot hide our traces so easily. Even a hundred million years into the future, there will be evidence that humans built cities upon this planet. (See The Earth After Us by Jan Zalasiewicz, who I mentioned in an earlier blog ‘The Carbon Trap’).
Astronomers use the techniques of spectroscopy to determine the composition of distant stars and galaxies. We have detected planets by observing minute changes in the amount and patterns of light from stars (several hundred have been found now). Some are Earth size and in the habitable regions of a star (see again ‘The Carbon Trap’ for the book The Goldilocks Zone by Jan Zalasiewicz and Mark Williams). Some of these planets – Earthlike or not – may be home to other civilisations. The search for extra-terrestrial life has not turned up any alien bones, even in the fragments of Mars that have arrived on Earth, but it is possible to consider an ‘aliensol’ as a marker for extraterrestrial life when we have developed techniques and modelled what an alien signature could be like. Current approaches focus on electromagnetic emissions, assuming that aliens would develop technology like ours, but this is limiting the imagination of our aliens to reflect what we consider to be important. (An alien version of TV ‘Neighbours’ perhaps…) . Christoph Adami has developed ideas from his work on artificial life in self-replicating computer programmes and his computer lifeforms – the ‘Avidians’ – to find ‘bio-markers’. I recommend the excellent TED talk: http://www.ted.com/talks/lang/en/christophe_adami_finding_life_we_can_t_imagine.html
Bio-markers are statistically significant shufflings of life-related components that produce a non-random distribution, indicating a preferential use or production of some of them that could be assiociated with the activity of life forms. Even the Avidians showed evidence of this.
The connectedness of this is that we find the ‘same old same old’ in our investigations, maybe not in familiar materials or contexts, but it gives us the power to extrapolate into unfamilar areas. I have often thought that the fundamentals of Artificial Intelligence, Search for Extraterrestrial Intelligence and imagined/re-envisioned worlds in literature, drama, film and art are the same. We are looking for ourselves.
And there, philosophically, is another ramble.