Category: Nutrition

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Pasta alle vongole

Some 160,000 years ago, with the Earth in the middle of an Ice Age, a group of modern-looking humans lived in a cave a few kilometers from the sea near the southern tip of Africa. There they huddled around hearths, chipped stone bladelets, and perhaps decorated their bodies or objects with a red pigment. The site, Pinnacle Point near Mosselbaai in South Africa, has just been unveiled to the public, and it is touted as the earliest evidence of human coastal settlement, and of our use of the sea’s resources as food. Yes, because our human troop in the cave also feasted on shellfish and other seafood. Anthropologists think that many similar sites existed, but that their remains have been washed away as sea level rose with the melting of the glaciers. The Pinnacle Point cave is now a sea cliff, 15 metres above the waves of the Indian Ocean.

The excavators of the site think that during the Ice Age savannah productivity was low, and human populations set out in search of better places to live, eventually finding them in coastal areas — which are now submerged, which is why no similar sites of this antiquity have ever been found. Shellfish would then have become a critical source of food, and the study contends that humans then followed these resources out of Africa, moving along the Indian Ocean coast to the Red Sea, the Middle East, and beyond…

As far as the cold waters of the North Sea, in fact. Fast forward to just a few thousand years ago: the late Mesolithic in northern Europe. In places like Britain and Denmark, humans still have a basically marine diet. Then agriculture comes, either in the form of knowledge or of farmers, and suddenly — the evidence is that the change was very rapid — the eating habits of 150,000 years are gone. That’s gotta hurt. In particular, what did people do about vitamin D, which is plentiful in seafood but in cereals, well, not so much. Vitamin D is made in the skin when it is exposed to sunlight. As Razib points out at Gene Expression, we know that genes for skin pigmentation have been strongly selected. Is it the sudden transition to low vitamin D foods in the Neolithic that accounts for the paleness of northern European skins?

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Seeds are not enough

An article in the NY Times tells a frustrating tale of agrobiodiversity use: stunning use by researchers, followed by disappointing use by farmers. It’s the story of Nerica ((The piece has been picked up elsewhere. The Economist’s Free Exchange blog also comments on it.)) — New Rice for Africa. This is a family of varieties derived in the 90s from a biotechnological breakthrough, the hybridization of African and Asian rice. ((Don’t get me wrong, these are not transgenics, though molecular methods were used to overcome the huge challenge of interspecific hybridization.)) Combining “the toughness of O. glaberrima with the productivity of O. sativa,” Nerica varieties have:

– Higher yields (by 50% without fertilizer, and 200% with).
– Earlier maturity (by 30-50 days).
– Resistance to local stresses.
– Higher protein content (by 2%).

A great example of researchers really unleashing the potential of genetic diversity. And one that has been rightly widely recognized. So why have the resulting varieties “spread to only a tiny fraction of the land in West Africa where they could help millions of farming families escape poverty”? It hasn’t been for want of trying:

To quickly move the NERICA technology into farmers’ hands, WARDA and its partners have adopted farmer-participatory approaches, such as the Participatory Varietal Selection (PVS) and community-based seed production systems (CBSS).

The NY Times piece suggests that the reason for Nerica’s disappointing use by farmers comes down to infrastructure. The seeds — even information about them — are not getting to the farmers that need them, and the harvest finds it hard to get to market. That’s because there are few seed companies, roads are bad, telecommunications poor, credit not available. The article also suggests that yield of Nerica has been known to decrease over time “because the new seed was not pure.”

It is undeniable that seed systems could be strengthened in Africa, and that doing so would improve the lot of smallholders. But I don’t know. Farmers are not stupid. They know how to select material for next year’s sowing, and they exchange seeds all the time, often over large distances. Their lives depend on it. Is there something else holding Nerica back? Or maybe it’s just too soon to be expecting miracles of adoption?