Deconstructing the spread of agriculture

Did agriculture move in the hands of people, or with the words of people? Or, somewhat more prosaically:

Two alternative models have been proposed to explain the spread of agriculture in Europe during the Neolithic period. The demic diffusion model postulates the spreading of farmers from the Middle East along a Southeast to Northeast axis. Conversely, the cultural diffusion model assumes transmission of agricultural techniques without substantial movements of people.

Actually not just Europe. And the jury is still out. Two recent paper both tilt towards cultural diffusion, both in Europe (which is where the above quote comes from; but not everybody agrees) and Island SE Asia. This sort of work is mainly done by anthropologists and human geneticists. Sometimes the genetics of livestock or crops are brought into play, but only rarely both at the same time. A grand synthesis of human, livestock and crop genetic data, archaeology and anthropology remains to be done…

Nibbles: Recognizing breeds, Cannabis in New Zealand, Farming systems data, Maize inbreds, Zinc in wheat, Markets for nature, Ramie, Milk and drought, ELBARN

Carnival of Evolution

There’s a new edition of the Carnival of Evolution up at Evolution: Education and Outreach, the “official blog” of the journal of that name, and it contains three items of direct interest to agrobiodiversity fans (four if you count our submission, but you’ve already read that, right?).

Nibbles: Rice, Tamil Nadu genebank, Seed Day, Olives, Nordic Cattle, Marmite, Musa, Butterflies, Congo

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. ((Not that that’s going to stop me taking my omega-3s.))

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.