Agrobiodiversity is crops, livestock, foodways, microbes, pollinators, wild relatives …
… to brag, we just have to.
Tim Bray, an internet seer, offered a definition of something he called a Power Web Site.
So, having nothing better to do over lunch, I took a little peek. And guess what? The Agricultural Biodiversity Weblog is a Power Web Site.
How gratifying.
I don’t know about you, but in my laziness I sometimes catch myself making the assumption that a centre of crop origin is also one of crop diversity. That is of course sometimes the case, but by no means always, as Vavilov himself recognized. A recent open access paper in Diversity makes the point very clearly. 1
The authors, led by Charles R. Clement of the Instituto Nacional de Pesquisas da Amazônia in Manaus, review molecular studies and also bring in archaeological and other evidence in their discussion of the history of Amazonian crops. They come to the conclusion that these crops originated around the periphery of the region: “All but one of the species examined originated in the periphery of Amazonia (Figure 3), rather than along the major white water rivers where pre-conquest population densities were greatest.” Here’s that Fig. 3:
Now, in contrast, here’s where the pre-Columbian hotspots of diversity were to be found: “The major centers and regions of diversity are along the major white water rivers and in northwestern Amazonia, where ethnic diversity is extremely high.”
The explanation, according to the authors, is the length of time involved in the development of agriculture in the region.
Because crop domestication began thousands of years before food production systems became important, it is not at all surprising to see a dramatic contrast such as that in Amazonia.
Why was the Amazonian periphery such a focus of domestication?
It is possible that sufficient natural resources were available [in central Amazonia] so that the home gardens were such a small fraction of subsistence that they are difficult to find in the archaeological record. In contrast, in the headwaters of the same rivers in the periphery, less abundant aquatic resources may have increased the importance of home gardens.
Dr Hari D Upadhyaya, head of the ICRISAT genebank, has just been honoured as a Fellow of the Crop Science Society of America (CSSA). Hari has done a huge amount of work on the theory and practice of core collections, among other things. Congratulations, Hari. Richly deserved.
A fascinating post from our friends over at The Ethicurean makes the case for backyard livestock as a valuable component of making life dirtier so as to avoid the diseases of cleanliness. Marc R. writes:
[R]ecent science is hinting that early childhood exposure to domestic animals can actually protect against the chronic condition [of asthma], so well-cared-for backyard animals like chickens or miniature goats could actually have an additional, unexpected benefit.
Marc goes on to summarize (and link to) various threads that address the “hygiene hypothesis,” a good starting point for anyone who wants to learn more about the possibility of strengthening the immune system by offering it a few more friendly sparring partners. To which I would add Seth Roberts on fermented foods, although the links to health take a little hunting down.
I’ve just received a copy of “Gene Flow Between Crops and Their Wild Relatives” by Meike S. Andersson and M. Carmen de Vicente (Johns Hopkins). This will no doubt become the go-to reference book on the subject. There are chapters on all the major crops, with what look to me like very comprehensive bibliographies on each. Of particular interest are the maps of introgression risk at the end of the book. These will apparently be made available on the Bioversity website in due course. But here’s one (barley) in the meantime to whet your appetite.
