Author: Luigi Guarino

You may recall a post a few days back on how domestic pig keeping spread into Europe. Well, Razib over at Gene Expression, a genetics blog, has a post today which includes a map of the spread of agriculture north and west from the Middle East. He points out that current thinking is that either the practice of agriculture did the spreading (cultural diffusion), or people themselves (demic diffusion) — or both. Both was what the pig work implied, of course. Human genetic studies suggest that Neolithic people have made a fairly low (maybe 20%) contribution to European ancestry, and Razib summarizes the current debate about whether that therefore refutes the hypothesis that movement of people was involved in the spread of agriculture, as well as that of ideas. Bottom line: it probably doesn’t.

He also links to a recent paper that calculates a figure for the rate of movement ((Tracing the Origin and Spread of Agriculture in Europe. Pinhasi R, Fort J, Ammerman AJ. 2005. PLoS Biology Vol. 3, No. 12. doi:10.1371/journal.pbio.0030410)): 1 km/year, give or take. That was arrived at by interpolating radiocarbon dates of Neolithic archaeological sites across Europe, and it fits very well with the results of models using human genetic data. ((As far as I’m aware, however, nobody’s done anything similar with crops.)) An interesting way to think about that speed of movement is that it is roughly a one-day walk per generation.