At https://phys.org/news/2023-11-modern-maize-hybrid-years-mexico.html … For some time the consensus has been that maize was domesticated from a single wild grass – teosinte. This is thought to have occurred in the lowlands of southern Mexico – by accident or by human experimentation, around 10,000 years ago. Presumably somebody noticed bigger seeds and made a point of saving some of them to reproduce more plants. More recently, geneticists have become aware that the genome of modern maize also contains DNA from a second teosinte wild grass that grows in the uplands of central Mexico. Hence, although maize was domesticated in the early Holocene it was not until around 5000 years ago that hybridisation occurred, with a maize that was the ancestor of modern varieties. At 5000 years ago we are at the Piora Oscillation – an event of some note but not easy to pin down. Did the temporary switch in global climate cause the mutation – and once again, did a human save the plant in order to reproduce it. The rest is history as they say. It is now a staple food.
At https://phys.org/news/2023-11-bone-biographies-reveal-medieval-england.html … which is a fascinating study of medieval bones – or bone biographies. It concerns residents of Cambridge from the 11th to 15th centuries – which you may note includes the outbreak of the Black Death plague. For more info go to https://doi.org/10.15184/aqy.2023.167 … which doesn’t seem to like WordPress. Alternatively, go to the new web site set up for the project at https://www.aftertheplague.org … and we may also note it includes the Great Famine years of 1315-1320 which decimated the human population because it was so wet crops rotted in the field. The plague quickly followed on from the famine and in a single year killed half the population, it is reckoned. The plague, however, was not a factor in the years prior to that or in most of the years after that single year. The biggest threat to life in medieval England, and this can probably be extended to western Europe in general, were chronic infectious diseases such as tuberculosis.
Scarcity of grain as a result of rotting led to higher prices. This put grain off the menu of a lot of people – and they died. Death caught up with a lot of those who could afford the high prices when the plague hit around 20 years later.