The sites are An Son, Loc Giang and Rach Nui. In all cases, conventional archaeobotanical evidence through macro-remains has been limited, although rice and millet as well as various wild taxa were reported from flotation at Rach Nui earlier this year. This makes the potential to recover plant remains from ceramic tempering quite tempting as an additional source of evidence on past plant use. As demonstrated by new evidence on sorghum domestication found in old sherds. However, while traditional we may cast impressions of those remains that are haphazardly represented on the surface, ct scanning allows full three-dimensional voids to be recovered from the interior of the ceramic fabric.
While patience and skill required to get such images is impressive, the results are breath-taking, with images of domesticated type, non-shattering rice spikelet bases pretty much as good as those found through flotation emerging (see left). It is not any surprise that these Neolithic folks in Vietnam were already dehusking fully domesticated rice and using the chaff to temper their ceramics-- this very much fits current hypotheses for the spread of fully domesticated rice into mainland southeast Asia from the end the Third Millennium BC (e.g. the recent review by Castillo in the journal Man in India). Methodologically, however, opens up the possibility for studying old ceramic collections from sites that may no longer be amenable to sampling through flotation or which lack good stratigraphy, at least so long as some ceramics are chaff tempered. This could prove quite useful for any earlier, less sedentary phases in the spread of rice, just as sherd impressions have proved so useful in Africa, right across the Sahara and sub-Sahara. Studying sherd impressions just got powerful new tool.