Oryza glaberrima not shatter, making the grains easy for humans to gather. A mutation that caused rice not to shatter would probably have been the beginning of domestication. Ibn Baṭṭūṭa recorded rice couscous in the area of present-day Mali in 1350. In the late fifteenth and sixteenth centuries, the Portuguese sailed to the Southern Rivers area in West Africa and wrote that the land was rich in rice. "<nowiki>[T]</nowiki>hey said they found the country covered by vast crops, with many cotton trees and large fields planted in rice … the country looked to them as having the aspect of a pond (i.e.,
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