Oryza sativa both "indica" and "japonica", Vaughan "et al." (2008) determined a single domestication event for "O. sativa" happened in the region of the Yangtze River valley. In 2003, Korean archaeologists alleged they discovered burnt grains of domesticated rice in Soro-ri, Korea, which dated to 13,000 BC. These antedate the oldest grains in China, which were dated to 10,000 BC, and potentially challenge the mainstream explanation that domesticated rice originated in China. The findings were received by academia with strong skepticism. Rice appears to have been used by the early Neolithic populations of Lijiacun and Yunchanyan. Evidence of possible rice cultivation in
Helitron (biology) Helitron (biology) Helitrons are one of the three groups of eukaryotic class 2 transposable elements (TEs) so far described. They are the eukaryotic rolling-circle transposable elements which are hypothesized to transpose by a rolling circle replication mechanism via a single-stranded DNA intermediate. They were first discovered in plants ("Arabidopsis thaliana" and "Oryza sativa") and in the nematode "Caenorhabditis elegans", and now they have been identified in a diverse range of species, from protists to mammals. Helitrons make up a substantial fraction of many genomes where non-autonomous elements frequently outnumber the putative autonomous partner. Helitrons seem to have a major role