What is Life? 1

So, in response to the invitation that concluded my last blog as to which topic should be the 'first up' out of:

1. Buy-to-let
2. Identity theft
3. Bitcoin
4. What is Life?

I can now announce the result, namely that 100% of respondents opted for topic no.4

Readers: You say respondents. How many were there exactly ?

Three as it happens; but it doesn’t matter. What is Life? it is.

Of course, by life, we could be talking about any number of things.  I mean, there's life in the abstract poetic sense:

What is this life if, full of care,
We have no time to stand and stare.
No time to stand beneath the boughs
And stare as  …..

Readers: Yeah, yeah — that's the one we want.

… then there’s the Hitchhiker’s Guide to the Galaxy Version ….

Readers: That one will do too. Whatever. Just get on with it.

But I’m not thinking of either of these.  No, I'm talking about life in the biological sense — what you see when you look at other people, dogs, trees, spiders, worms, flies. slugs and slime ... that sort of life.

Readers: Heaven preserve us.

And so the question is .... what is it exactly. What is life ?

(Some people, sensing an imminent plunge into something resembling a school chemistry lesson, might choose to get off at this point. If you are one of them then please don’t feel badly about it; it’s not like I’ll ever know. Just try to leave quietly without upsetting the others.)

I have been interested in this topic for a number of years. It would be reasonable to ask why.

Readers: Maybe — but do we really have to ? 

I could talk about the books I have read, about theories and scientific disciplines but that would be to miss the essential thing, which is  more to do with the sense of wonder we experience when we stand back and contemplate the mysterious world that surrounds us. And so it was in my case, initially through literature and film — and in particular, Stanislaw Lem’s book, Solaris and the later film adaptation by Andrei Tarkovsky — that I first caught a glimpse of the world seen as a stranger or innocent might see it.

In Lem’s story, the planet Solaris is so unfathomably complex that entire institutes are established, dedicated to the study of the bizarre and incomprehensible processes and structures observed on its surface. The consensus view is that the planet is effectively a single, sentient organism and, though this was some years before James Lovelock’s Gaia, it didn’t take a huge leap of the imagination to see that Solaris might easily be taken to stand for our own planet. In the film version Tarkovsky takes this a step further, in making it clear how those who have experienced the planet firsthand are irrevocably changed by the experience — being left with the sense that things formerly seen as ordinary or commonplace have taken on a quality of profound mystery.

Then sometime later, I was watching a wildlife documentary in which a flock of white birds, filmed from above, was flying over an empty  landscape and I found myself thinking how Earth is a planet on which the basic building blocks of matter have mysteriously become alive to the extent that pieces can actually detach themselves from the surface and engage in all sorts of complex behaviours. In truth, Earth itself is a living planet - not just a planet with life on it, but a planet that is itself alive; seemingly unique among the other planets in the solar system; and, for all we know, in the entire universe.

In attempting to explain life, scientists — at least until recently — have had little to offer beyond the idea that, given sufficient time, the generation of a mind-boggling number of random combinations of molecules will eventually result in the accidental creation of one or more exquisite biological mechanisms, capable of self-organisation and replication.

Meanwhile, to people of faith, it is all down to the hand of God — it being utterly inconceivable that the rich tapestry of life could have come about by means of a mere lottery, however many rolls of the balls are allowed.

I find both of these views — which could respectively be labeled creationist and mechanistic — completely unsatisfactory, inasmuch as they regard the material world as oddly limited in its capacity to give rise to new forms and structures. In both scenarios, the laws of physics and chemistry are allowed to explain certain natural combinations: molecules, crystals — even amino acids (the building blocks of proteins) but it is as if, beyond a certain level of complexity, further structural elaboration is assumed to be implausible and something else has to be brought into play: either God or Dawkins’ blind watchmaker.

There is another alternative however: namely that it is in the nature of basic matter to assemble itself, first as simple and later more complex molecules, all the way up to the astounding nano-machines found in even the simplest cells and that this process entails a rich interplay of structure and environment — subject, all the while, to a number of simple rules. This is discussed in a recent book by Nick Lane: The Vital Question. As I have only a rudimentary understanding of chemistry, I have found the book fairly hard going and am still only around halfway through reading it, but it is inspiring to see the author explain how the fundamental processes found in the simplest bacterial forms of life might have come about almost inevitably, given the right environment.

Readers: so that’s what you spend your time thinking about … 

Well not all my time exactly, but yes - and for no other reason than that I find this stuff seriously fascinating. And what’s more, it raises all sorts of interesting questions — for example:

Evolution would appear to account for the ‘endless forms’ in which life manifests itself, but the underlying mechanisms governing replication, respiration etc are virtually identical in all living species - even the most primitive. How did such mechanisms themselves evolve and why are there virtually no traces of alternative designs ?

Readers: Why indeed ?

And is life on earth unique or does it exist elsewhere in the universe?

Readers: Yes — that’s a good one and what’s the answer do you think ?

Ah - we might have to leave that till next time.

Readers: What? There’s more ? 

Lots. We’ve barely scratched the surface