Thursday, May 17, 2007

Survival of the likeliest?

There's a feature by me in the current PLoS Biology (and it's free!) on whether natural selection can be explained by the laws of physics, specifically thermodynamics and statistical mechanics. This looks at work of Roderick Dewar on Maximum Entropy Production (MEP), Adrian Bejan's constructal theory, work by Eric Smith at Santa Fe on self-organization and metabolism, and a few other things. The basic idea is that, by looking at the flows of energy and matter, we can predict and quantify the path and results of evolution.

This is something I've been thinking about for a couple of years — I put a bit about it in the first draft of ITBOAH, but took it out, 'cos it wasn't really working. And I wrote a piece for Nature looking at MEP from a more climate- and ecological viewpoint, which didn't go so much into the evolutionary implications. So I'm very glad that this is finally seeing the light of day.

What I did on my holiday

I've just got back from three weeks on holiday in Andalucia. Two things I learnt:

Trenhotel good. If you don't dilly-dally, you can eat lunch in London one day, and in Seville the next, without leaving the ground. The overnight journey, from Paris to Madrid, is comfy and fun (cf flying) – there's a bar and restaurant on the train. The mighty has all the details.

Plasticultura bad. When I saw vegetables in my local supermarket from Spain, I had, I suppose, a dim image of a happy campesino weidling a mattock and whistling a song. In fact, it seems that they are grown in one of a never-ending series of plastic greenhouses that, in eastern Andalucia (around Almeria) fills just about every bit of land between the sea and the mountains.

There's a danger in knee-jerk disapproval of the unsightly — I'm sure there are outdoor forms of farming that have just as much environmental impact, but, because they fit our idea of what farmland should look like, don't make you as depressed as a sea of plastic. And there are arguments that, where we farm, we should do it as intensively as possible, so that is uses the minimum of land and leaves more for nature (whatever one means by that). (Although in a country like the UK, where farmland and countryside are the same thing, this would be tricky.) Plasticultura, or invernaderos, however, do seem to take out more water, and put back more nitrates, than the land can support. Plus they are hellish places to work (although not so hellish that no one wants to work there).

To find out more, try this article from the Ecologist for more on water, the environment and farming in southern Spain, this from John Vidal on the Spanish drought, this lecture by Felicity Lawrence for intensive farming in general, and here (recommended) for photos of plasticultura farming.

I shan't be buying Spainsh veg any more, thus making my winter diet even more cabbage-based than previously.

Oekologie #5

Jeremy Bruno over at the Voltage Gate has done an erudite job on this month's Oekologie blog carnival (my own hosting effort is here).