Oryza glaberrima conditions, filling, and has a distinct nutty flavour. It is also grown for cultural reasons; for instance, it is sacred to awasena followers among the Jola people, and is a heritage variety in the United States. Crossbreeding between African and Asian rice is difficult, but there exist some crosses. Humans have independently domesticated two different rice species. African rice was domesticated from wild African rice, "Oryza barthii", while Asian rice ("Oryza sativa"), was domesticated from wild Asian rice, "Oryza rufipogon". "Oryza barthii" still grows wild in Africa, in a wide variety of open habitats. The Sahara was formerly wetter, with
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