I’ve been hoping to get back to my Peasant’s Republic of Wessex, albeit by a roundabout route, but it’s busy days on the farm at the moment so it’ll have to wait. Instead let me offer a few scattered thoughts to follow on from the discussion last time of RoboBees, nature vs humanity and Clem’s enthusiasm for photosynthesis – thoughts prompted by an article in the New Scientist that I recently read under the misapprehension that it was hot off the press, only to find after drafting this post that it was published nearly three years ago (but still, I think, a propos). Never let it be said that Small Farm Future isn’t bang up with the latest science…
Anyway, where I want to go in this piece ultimately is some mildly philosophical thoughts on nature and farming, and on holism and reductionism, and the links between these two dualities – thoughts with some upbeat implications for a small farm future. But first I’m going to have to take you through another ecomodernist vale of tears. So for those of a nervous disposition – be warned.
My starting point is that trusty old ecomodernist standard that photosynthesis – the process at the foundation of complex life on earth by which plants convert solar energy and carbon dioxide into the chemical building blocks of their tissues – is chemically inefficient and can be improved by human bioengineering. I’ve heard this point made quite often without further elaboration in the ecomodernist circles that I eavesdrop into from time to time, and my instinct has always been to dismiss it as a typical example of ecomodernist hubris.
But in the New Scientist piece I mentioned, Michael Le Page gives a slightly more detailed overview than usual of the issue, and reports on research that he says has “taken a huge step forward” in engineering improved photosynthesis by inserting a faster-photosynthesising version of the key RuBisCo enzyme from a cyanobacterium into a tobacco plant1. From here, Le Page leaps to the favoured productivist ideology of the ecomodernists, arguing “This seems like great news in a world where demand for food, biofuels and plant materials like cotton continue to increase, and where global warming will have an ever greater impact on crop production. More productive plants mean greater yields”. Then, he makes another huge leap of logic…but I’ll come to that in a moment.
I’m not a biologist so I’m going to frame the issue to the best of my limited abilities and put out a call to anyone better grounded in this than me to put me right if my reasoning is flawed. So, as I understand it, the chloroplasts in plant cells where photosynthesis occurs derive originally from free-living cyanobacteria, as Le Page describes. At some stage in the evolutionary past (though not, I think, ‘a billion years ago’ as Le Page claims) some such cyanobacteria were incorporated into the cell architecture of ancestral plant species. They’ve retained some, but not all, of their original DNA independently of the plant’s, but the plant cells see to it that they live in a cossetted, beneficial environment (they know which side their bread is buttered) and the result is that chloroplasts turn over and mutate at a slower rate than free-living cyanobacteria, which are more subject to direct evolutionary selection pressure. My guess is that this is what Le Page is driving at when he says that the “enslaved cyanobacteria” of plants have had “little scope to evolve” and are therefore less well adapted to today’s relatively carbon dioxide impoverished environment than free-living cyanobacteria which “have been able to evolve unfettered”.
But it’s not as though plants haven’t innovated evolutionarily in photosynthetic matters. As Le Page himself points out, plants have evolved the more efficient C4 photosynthetic pathway – in fact, this has evolved independently at least 31 times within various plant genera, mostly in the warmer climates where the C4 pathway works best. So why have plants been able to evolve more efficient forms of photosynthesis but not the super-efficient ones of the cyanobacteria? I don’t know, but my guess would be it’s not because the ‘enslavement’ of their cyanobacteria makes them evolutionarily unadventurous (which strikes me as the misguided application of a human metaphor to the natural world). Even if mutation in chloroplasts turns over more slowly than in cyanobacteria, plants have been around a very long time and, other things being equal, the advantages of more efficient photosynthesis are such that just a few mutations along these lines across the whole history of the plant kingdom would quickly propagate itself. So my guess is that ‘other things’ aren’t equal. Or to put it another way, plants are not reducible to their chloroplasts – there are numerous forces acting on the whole plant which it has to deal with as a complete organism in its environment. And these doubtless create trade-offs for the plant between photosynthetic efficiency and other desired characteristics – maybe drought tolerance and speed of growth?
If that’s so, it still doesn’t mean in itself that it’s necessarily a bad idea to engineer more photosynthetically efficient plants. But it suggests that the resulting plants may not be so well adapted to other aspects of their environment. And this, in a nutshell, is the tragedy of agriculture. For example, wild cereals would never naturally evolve the characteristics bred into them to suit human purposes – namely, short stems to ensure that as much of their photosynthate as possible goes to the desired seed, and non-shattering rachis to ensure that as many of the seeds as possible go into the desired grain harvester. Put such a plant into a wild grassland and it would be instantly outcompeted by tall-stemmed, shattering varieties – which is why farmers have to spend their days ploughing, weeding, spraying and so forth. My feeling is that Le Page’s “supercrops” with their “turbocharged photosynthesis” will only be “super” when they’re cossetted in the field or garden – just like other genetic monstrosities such as the bread wheats that humans have created down the ages.
If I’m right it may be a blessing, because Le Page thinks otherwise – in his view, these supercrops may outcompete wild plants, and the inference he draws is that we should not only let them do so but actively promote this outcome, in his words by “upgrading many wild plants too”. His rationale for the ‘upgrade’ of crop plants is the familiar ‘land sparing’ argument: in his words, “boosting agricultural yield to feed more people with less land”. And his rationale for the wild upgrade is this: “Wild animals need to eat too, and we’re not leaving much for them. An ecosystem based on superplants would support more life overall”.
Well, that suggestion leaves me as outraged as the next right-thinking greenie, but I want to focus my attention on the logical structure of this argument, which I find curious. At issue is an old debate in ecology as to whether the assemblages of organisms we call ecosystems have some emergent higher-order structure – whether the ecosystem is, as it were, a ‘superorganism’ – or whether it’s a more random, dynamic and competitive order with no equilibrium state or baseline by which we can say ‘Ah, here’s a proper ecosystem – intact and in balance’. The current orthodoxy in ecology, as I understand it, inclines towards the latter view, as elaborated for non-specialist audiences by the likes of Andy McGuire and in Emma Marris’s book Rambunctious Garden2.
Marris’s book has a cover endorsement from ecomodernist granddaddy Stewart Brand, and I suppose it’s not hard to see why. If there’s no stable ecological baseline, no ‘right’ ecosystem, against which to judge human fiddling with the rest of the biota, then there can be no objection in biological principle to any kind of bioengineering or plant ‘upgrade’ that somebody might deem worth a shot. But that argument cuts both ways. By the same token, there can be no objection in biological principle to filling the countryside or even the national parks with peasant farmers pursuing a putatively less ‘efficient’ form of ‘land sharing’ agriculture. The relatively efficiencies of high-tech commercial agriculture and low-tech peasant agriculture are difficult to determine, and it’s by no means a given that the former outscores the latter. But the beauty of the ‘random ecosystem’ argument is that it doesn’t matter. If it were true that the natural world was a thing of delicate balance entirely outwith human affairs that was apt to collapse in a heap at the hint of human presence, then I could see the logic of the ecomodernist position, at least theoretically – get people into cities well away from ‘nature’, grow food in the most efficient, lowest land-take manner possible, go vegan etc. In practice, I don’t think this is a good idea because for numerous reasons I think human environmental impacts in the long-term and possibly even the short-term will be greater, not lesser, if we go down this route. But theoretically at least, it’s a position that might make sense. If, on the other hand, we accept that humans are a part of the natural world and will inevitably affect it, just as all other organisms do, then the logic of ‘sparing’ land for nature becomes harder to discern. Of course, humans affect nature disproportionately to our numbers (or perhaps a better measure would be to our biomass), so whether we’re ‘sparing’ or ‘sharing’ it’s surely a good idea for us to attend to our impacts on the natural world – but there’s nothing written in the book of nature that tells us what those impacts should be. So there’s no ecological rationale for Le Page’s plan to ‘upgrade’ wild plants so that wild animals have more to eat.
Maybe what’s going on here is another set of contradictions around another dualistic debate – holism versus reductionism. We face some big, broad problems in the world – like how to feed humanity sustainably. Meanwhile, the scientific method has been spectacularly successful at understanding the world not so much in a big, broad holistic way, but in small, particular, reductionist ways. The problem with ecomodernism as I see it is that it makes the characteristically ‘modernist’ category error of trying to resolve the duality by addressing the general from the particular, by solving big, broad problems using small, reductionist means. I’d like to propose the opposite approach, of trying to solve small, particular problems by big, broad means. Take any person in the world – what are the main problems they have to solve as an individual to live well? How about food, clothes, shelter and conviviality? And what are the main factors obstructing them? I don’t think the photosynthetic inefficiency of the eukaryotic cell tops the list.
When I published my critique of the Ecomodernist Manifesto somebody tweeted a response along the lines of “Not beyond the wit of humanity to solve our problems. Maybe beyond the wit of @csmaje.” Well, it certainly is beyond my wit to solve humanity’s problems, and I’m inclined to think that it’s also beyond humanity’s collective wit to solve its collective problems. But then again I don’t have to solve humanity’s problems, and nor does anyone else. Solving my individual problems concerning food, clothes, shelter and conviviality stretches my wit quite enough, but at least it seems potentially achievable. So my contention for debate is this: IF WE COULD ONLY STOP TRYING TO SOLVE THE PROBLEMS OF THE ‘WORLD’ AND FOCUS ON OUR OWN DANGED PROBLEMS, THEN THE WORLD WOULD BE A LESS PROBLEMATIC PLACE.
Let me be clear: I’m not arguing that we shouldn’t care about other people or other beings; I’m not arguing that we shouldn’t work collectively with others; I’m not arguing that private vice equals public virtue, along the lines of Adam Smith. One of the ironies of the Smithian position is that it takes a strong, universalist body like a centralised state to break down local connections sufficiently to enforce the pursuit of ‘private’ self-interest. I’m just arguing that specific problems addressed holistically at the local level may prove more tractable than general problems addressed specifically at the global level. All of those terms are up for debate, but my starter for ten would be that small-scale, local, ‘land-sharing’ agroecological farming based on tried and tested materials and methods will do a better job of feeding the world and the rest of the biota too than Le Page’s superplant upgrade. And I say that in full awareness that there are various major global crises underway, including mass extinction. I agree with Le Page that “we are way, way past the point where we can preserve Earth the way it was before we came to the fore”. I just don’t think particularistic solutions to holistic problems of the kind he offers will best overcome them.
In his book Darwinian Agriculture – my go-to text for sensible scepticism about the wilder claims of both biotechnology and ‘alternative’ agriculture – ecologist Ford Denison reports that the claim to be able to engineer improved photosynthesis has been around for about forty years and is not likely to be realised “anytime soon”3. After discovering that the cyanobacteria ‘upgrade’ of tobacco wasn’t exactly the latest news, I spent a bit of time searching the web for an update on this breakthrough – not so diligently that I can be sure of this, but I failed to turn up anything published within the last year or two to suggest that the ‘upgrade’ was closer to reality. Could this be yet another one of those fabled ecomodernist technologies, like nuclear fusion, destined to recede ever onwards into the almost theres of the future? If you can bring me any further news of this particular hereafter, I’d be happy to hear it…
Notes
- Michael Le Page. 2014. Turbocharge our plants. New Scientist. 224, 2989: 26-7.
- Emma Marris. 2011. Rambunctious Garden: Saving Nature in a Post-Wild World. Bloomsbury.
- Ford Denison. 2012. Darwinian Agriculture: How Understanding Evolution Can Improve Agriculture. Princeton: Princeton University Press.
Teaser photo image: Wikimedia Commons, coniferconifer from japan under a Creative Commons 2.0 License.
