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Tomatoes in Ghana

Cotton farmer suicides in India get all the press, but three years ago we noted briefly the apparent suicide of tomato growers in Ghana. Today sees a meeting in Accra “for a unique exchange of views on how to revive the strategic but ailing tomato sector.” Farmers, traders, processors, academics and donors will be thrashing out a more strategic approach to the tomato sector in Ghana under the watchful eye of the Ministry of Food and Agriculture and IFPRI (the International Food Policy Research Institute). IFPRI anticipates that:

Improvements across the board could reduce Ghana’s reliance on low-cost imported tomato paste, improve its foreign exchange reserves, and provide employment and development opportunities in poor rural areas.

How many wins is that?

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Vaccines, vitamins and er .. lemme see .. vital information!

Michael Specter is a staff writer for The New Yorker, has a book out called Denialism: How Irrational Thinking Hinders Scientific Progress, Harms the Planet, and Threatens Our Lives, and gave a recent TedTalk on The danger of science denial that has created quite a stir, most of it positive. And I’m mostly in accord.

People who refuse to vaccinate their children are indeed free-riding anti-social parasites, no matter what cockamamie reasons they give for their refusal, and those who aid and abet them by stoking fears about the dangers of vaccination are, if anything, worse, because their stupidity is a multiplier that endangers so many more of us.

And yes, people who spend (lots of) good money on vitamins and quack cures and other folderol that is not only not efficacious but sometimes downright harmful are indeed fools, easily parted from their money and probably suffering into the bargain, let alone the leeches who prey on them. 1

But — and here, at last, is where we approach the admittedly catholic tastes of this blog — when Specter turned to the denialism that, he says, condemns million of hungry people to miserable starvation and an early death, I got just the teeniest whiff of inconsistency. What were his chosen examples for the evidence-based decision-making that he wants us to embrace not only for vaccines and vitamins but also for the vital business of feeding people with GMOs? Golden rice and super-cassava.

I kid you not.

It’s true that modern rice varieties lack vitamin A precursors. It’s also true that golden rice 2.0 delivers more carotenoids than version 1.0. But so do many other foods that people can actually grow for themselves, that a diversified agriculture and diet can provide and that are almost certainly cheaper and more sustainable than golden rice. So where, precisely, is the evidence that golden rice is the best, or even a good, solution to the problem of vitamin A deficiency? Specter seems completely unaware that the alternatives even exist, let alone that they could be made available now, everywhere.

Likewise, Specter may not rate cassava all that highly, but the plant provides people with far, far more than the the “empty” calories that Specter assumes. For a start, cassava leaves are widely eaten, and supply many of the nutrients lacking in the tubers. I remember someone telling me that leaves infected with cassava mosaic virus may actually be more palatable and more nutritious than uninfected leaves (although I confess I cannot now find the details). Will one engineered super-cassava be suitable for all the places where it will be needed? How easy will it be to create the huge diversity of super-cassavas that Africa’s diverse growing conditions require?

Let me be absolutely clear. I am not against genetic engineering at all. How could I be, when it is only a tool? Indeed, I think that there are far more pressing problems than fortifying staples that deserve and are being denied a genetic engineering approach. I am not denying that one could deliver more vitamin A and other micronutrients by engineering rice and other staples. I am denying that this is the only way, or even a good way. We’ve been round and round these discussions here and elsewhere. What we really need, and what, I fear, Specter does not want, is a little more investment in the alternatives. It might even prove that I’m completely wrong. In which case I swear I’ll change my mind.

That’s how I use evidence.

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Crossing the Wallace Line

Dienekes’ Anthropology Blog has an intriguing map from a paper on human genetic diversity in island South East Asia showing a sharp cline across Wallace’s Line.

The genetic cline corresponds to a cline in phenotype which was actually recognized by Wallace himself. 2 The authors…

…conclude that this phenotypic gradient probably reflects mixing of two long-separated ancestral source populations—one descended from the initial Melanesian-like inhabitants of the region, and the other related to Asian groups that immigrated during the Paleolithic and/or with the spread of agriculture. A higher frequency of Asian X-linked markers relative to autosomal markers throughout the transition zone suggests that the admixture process was sex-biased, either favouring a westward expansion of patrilocal Melanesian groups or an eastward expansion of matrilocal Asian immigrants. The matrilocal marriage practices that dominated early Austronesian societies may be one factor contributing to this observed sex bias in admixture rates.

There’s a map of the same region in the recent paper on pig domestication that’s been in the news lately.

Compare and contrast. Still two quite distinct populations, but the placing of the line of demarcation is somewhat different. This is what the authors have to say about the Pacific pigs, after their main discussion, which is of their separately domesticated Chinese cousins:

This genetic evidence also supports separate domestication pathways (however independent) of one population in India and three wild boar populations indigenous to Peninsular Southeast Asia. Given the relative geographic proximity of the Southeast Asian clades, it is possible that the domesticated haplotypes were all present in a single population of wild boar, as is the case for modern Yaks. Regardless, only the Pacific Clade domestic pigs were transported out of Southeast Asia (to ISEA and the Pacific) before they were replaced in their homeland by domestic pigs derived from nonindigenous populations of wild boar.

So, people and pigs moving together across Wallace’s Line. How about crops? There are also distinct Pacific and Asian genepools in taro, though I could not find a nice map to compare directly with the above. However, the consensus seems to be — as also for crops such as bananas, yams, breadfruit, sugarcane and yams — that domestication happened southeast of the Wallace Line, in Sahul (Melanesia to be exact). As my friend and colleague Vincent Lebot said of these crops a few years back 3:

We now have biomolecular evidence to suggest that most cultivars were not brought by the first settlers from the Indo-Malaysian region, but rather were domesticated from wild sources existing in the New Guinea and Melanesian areas… In other words, the first migrants that went across Wallacea did not embark major domesticated plants if any, in their adventure.

Pigs, in other words, and maybe chickens, but not taro or yams. Banana went in the opposite direction. I wonder why. Or did people bring them on their adventure, and abandon them when they found better varieties?

Incidentally, coconut also shows a bit of a Wallacean dividing line, but of course it doesn’t need humans for its dispersal, at least not everywhere.

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Quibbling while the world burns

The Soil Association has an ax to grid, sure. But it seems also to have a point — sort of. In a report out a couple of days ago it notes that people have been saying that people have said that food production needs to double by 2050, because of population increase, westernization of consumption patterns and climate change. It then goes on to suggest that people have not said that at all, and that other people should stop saying they had.

Research into the doubling figure shows it doesn’t actually exist in the stated source — and that it is based on a number of incorrect assumptions. The scientific basis for the claims are based on a report which on close inspection actually says production would need to increase by around 70%, not 100%. As the Government states this is a significant difference. The closest the report comes to the doubling claim is projecting that meat consumption in developing countries, except China, could double. The scientific paper that the 50% by 2030 claim is based on appears to have been withdrawn by the authors.

So, first, is this a straw man? It seems not. People really have been quoting the doubling-by-2050 figure.

Second, is it true that the key document usually cited as the source, FAO’s 2006 publication World Agriculture: Towards 2030/2050, does not make the doubling claim? Well, you can check for yourself, but I did some rapid searching and found no such claim. The only reference to a doubling or 100% increase by 2050 came in the context of meat consumption in developing countries (minus China) on page 5.

Some of this growth potential will materialize as effective demand and their per capita consumption could double by 2050, i.e. faster than in the past. It is unlikely that other major developing countries will replicate the role played by China in the past in boosting the world meat sector.

The Soil Association report says that the “only specific statements [in the FAO document] about large percentage increases in demand are focused on the developing world (where the increases in population will be) and concerned only with meat and cereal production, not all food.” In particular:

The largest projected increases in food demand are for cereals and for meat and dairy products. For cereals, there is a projected increase of 1 billion tonnes annually over the 2 billion tonnes of 2005, a 50% increase in cereals by 2050.

Which seems an accurate enough precis of the statement on page 5 of the FAO document:

…an increase of world production by another 1.1 billion tonnes annually will be required by 2050 over the 1.9 billion tonnes of 1999/01 (or 1 billion tonnes over the 2 billion of 2005).

But. FAO also says that “the absolute increases involved should not be underestimated” and “[a]chieving it should not be taken for granted, as land and water resources are now more stretched than in the past and the potential for continued growth of yield is more limited.”

So, sure, a 50% increase in cereal production in developing countries is not the same as a doubling of food production globally, and we should not use figures for which the evidence is thin at best. But it still represents a significant challenge, in particular to breeders. I hope the Soil Association is going to help the world meet it, and not just snipe from the sidelines.