A possible record of human evolution

Region / Crop Common Name Earliest Date (approx) Radiocarbon years BP 

A further point of interest in the East China Sea stratigraphy is the initial occurrenee of phytoliths at 13,900 years ago and then their absence from the sediments dated between 13,000 and 10,000 years ago. This latter period was characterized by a return to relatively cold conditions following rapid warming as the last ice age ended. This climatic deterioration may have resulted in an abandonment of rice cultivation which was resumed after 10,000 years before the present. 

Another centre of crop domestication was sub-Saharan Africa but evidence is scarce. Diamond (2002) recognises three centres of plant domestication tropical West Africa, the Sahel and Ethiopia. Tef, a cereal, derives from the latter while pearl millet and sorghum, also a cereal, originated in 

Today agricultural systems are varied and widespread, as discussed in Section 6.2.1. 

No part of the empire smwived without introduced plant and animal species. Some of the species introduced to Britain, one of the more distant colonies of Rome, are listed in Table 5.2. Many species were and continue to be widely cultivated. In addition, archaeological sites of Roman age attest to the importation of exotic crops and commodities. For example, excavations near the Thames in London, which developed into a major trading centre in the Roman Empire, have revealed the presence of 

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