Flint Dibble on archaeology: what the evidence says · JRE #2136
SUBJECT: ARCHAEOLOGY
Not a true/false call. Every claim is logged with its sources; read the exhibits below.
We have evidence against it from those pollen cores, but also this article by Peter Richardson and colleagues points out that agriculture, it was probably too hostile of a condition for agriculture in the ice age. The reason why is because there's too little CO2. Plants need carbon dioxide to be able to propagate and grow and be grown intensively in particular.
What the evidence says 01 / RECORD
Dibble faithfully summarizes Richerson, Boyd and Bettinger (2001), Was Agriculture Impossible during the Pleistocene but Mandatory during the Holocene?, published in American Antiquity 66(3): 387 to 411. That paper argues that ice and ocean core proxies show last glacial climates were extremely hostile to agriculture (dry, low in atmospheric CO2, and highly variable) and hypothesizes that agriculture was impossible under last glacial conditions, with low CO2 as one of the limiting factors. The underlying plant physiology is supported: a peer reviewed meta-analysis finds that a roughly 50 percent reduction in CO2 to glacial levels near 180 ppm cut plant dry biomass by about 47 percent, and links the later rise to 280 ppm to the emergence of agriculture. The one error is the author's name, which is Peter Richerson, not Richardson, a minor misstatement that does not affect the substance of the claim.