Timeline of plant evolution to the present. In Jericho (modern Israel), there is a settlement with about 19,000 people. At the same time, Sahara is green with rivers, lakes, cattle, crocodiles and monsoons. At 8 ka, Common (Bread) wheat ("Triticum aestivum") originates in southwest Asia due to hybridisation of emmer wheat with a goat-grass, "Aegilops tauschii". At 6.5 ka, two rice species are domesticated: Asian rice, "Oryza sativa", and African rice "Oryza glaberrima". Timeline of plant evolution This article attempts to place key plant innovations in a geological context. It concerns itself only with novel adaptations and events that had a major ecological significance,
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