A paper just out in Quaternary Science Reviews provides an overview of the first 3000 years of the spread of cultivated cereals around Eurasia, based on archaeobotanical evidence. The paper has some nice maps, but the press release has a really cool animated gif, which I had no hesitation in stealing.
Here’s a quick summary:
- Before 5000 BCE: farming communities used foothill, alluvial and catchment locations in different parts of Eurasia.
- Between 5000-2500 BCE: crops move around, but remain ecologically constrained, with the Tibetan Plateau and the Asian monsoons separating east from west, and north from south.
- Between 2500-1500 BCE: crops are taken to new thermal and hydrologic contexts, bringing previously isolated agricultural systems together.
And where are we now? Well, for that you need another new paper, this one in PLOS ONE: Regional and global shifts in crop diversity through the Anthropocene. As luck would have it, three phases here too, covering the past 50 years:
- little change in crop diversity from 1961 through to the late 1970s
- a 10-year period of sharp diversification through the early 1980s
- “levelling-off” of crop diversification beginning in the early 1990s
No gif, alas, but there’s a little video accompanying the press release in which the author summarizes the results.
The title of that press release says it all really: “A small number of crops are dominating globally. And that’s bad news for sustainable agriculture.” Compare and contrast with the findings of Colin Khoury and friends from a couple of years back on the increasing homogeneity of global diets. Basically looking at the same data in a somewhat different way: pretty much the same result.