The Evolution of Wheat - Bread Wheat
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 Spelt, itself an amphiploid hybrid between Emmer Wheat and a Goat Grass, was a hard hulled type of wheat. However, about 8,500 BP, a fortuitous natural mutation changed the structure of the Spelt spike or ear. The ear became roughly square in section, with more grains and a tougher rachis. More importantly, the hard hull enclosing the grain mutated to a softer shell that would break away when threshed, thus releasing the grains. This free-threshing hexaploid hybrid evolved further to become the source of our modern Bread Wheat, Triticum aestivum.

Initially the farmers grew wheat from seed they had saved the previous year. This created many different "land races", each being a selection of wheat suited to the type of soil or area where it had developed. Wheat scientists later selected and developed many improved varieties of wheat. In Britain, this gave an increase in yield from about 500 kg/ha in the 1300's, up to 1,000 kg/ha in the 1800's,  2,000 kg/ha by 1914, and up to 8,000 kg/ha in 2000 using newer varieties.