Nitrification is the oxidation of ammonia to nitrite. It’s an important part of the nitrogen cycle and all that, but bad news for agriculture, because up to 70% of applied N fertilizer can be lost to plants this way. There are synthetic nitrification inhibitors out there (e.g. dicyandiamide), but now comes news that a wild relative of wheat is also pretty good at slowing down the process. Researchers have identified the bits of the genome involved in biological nitrification inhibition in Leymus racemosus, and have managed to get them to do their stuff in wheat too. ((Subbarao, G. et al. (2007) Can biological nitrification inhibition (BNI) genes from perennial Leymus racemosus (Triticeae) combat nitrification in wheat farming? Plant Soil 299:55-64.)) Is there nothing crop wild relatives can’t do?
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?
Two Africas
While browsing the iafrica.com website after reading its features on the potato, I ran across an article about tea-tasting at the Mont Rochelle Hotel in Franschhoek, not far from Cape Town. Which sounds wonderful. But a poignant complement to it was provided by a post I found a little bit later on a blog from the Botswanan village of Nata, which has a line about how tea and bread are served at funerals there. Anyway, Nata Village Blog seems like it’s definitely worth following. Franschhoek and Nata are about 1,600 km apart, as the crow flies.
Crop books reviewed
More about food and farming from bookforum.com, including links to reviews of books on the history of citrus and of beans. Meanwhile, iafrica.com has features on the potato in history and the potato and politics to remind us that 2008 will be the International Year of the Potato.
Kill and cure
There’s a great article at Common-Place about the Great American Ham. No, not Kevin Bacon. We’re talking how to cure “the thigh of a back leg of a hog, [with its] three large cross braided muscles, now designated the inside round, outside round, and sirloin tip.” It’s down to the “three s method: salt, saltpeter and smoke.” Sugar sometimes features as a fourth s. Fascinating historical stuff, and something of a (welcome)Â antidote to our incredibly popular mini-pig nibble.