At https://tallbloke.wordpress.com/2020/05/15/global-cooling-event-4200-yea… … a global cooling event 4200 years ago spurred the evolution of rice which then spread across Asia, we are told. The cooling event is the well known 2300BC event with a low growth tree ring anomaly at 2345 and again, at 2200/2150BC. Moe Mandelkehr in one of his SIS articles catalogued a considerable amount of long distance migration that occurred at this time. In the new study the crisis led to the development of improved rice varieties.
Rice was first cultivated 9000 years ago, it is thought, in the Yangtse river valley. The spread of rice by humans probably had more to do with migrations of people, as well as long distance trade networks, than simply an improved strain – but the two seem to go together. It went from China to Korea and Japan for example, and soutwards into SE Asia. The map below is at www.eurekalert.org/multimedia/232077.php …
At https://phys.org/news/2020-05-early-humans-south-african-landscape.html … early humans in South Africa occupied what is now a submerged continental shelf system off the bottom of Africa. People in the Late Pleistocene, or Ice Age, if you like, were living on the continental shelf, which surpringly was not very cold, but decidedly warm and comfy. Changes in sea level associated with the end of the Ice Age drowned a landscape replete with rivers, fertile soils, savannah grassland, floodplains and woodland etc, teeming with animals such as hippos, zebra, antelope etc. It was a lush landscape in an icey world – and not altogether too distant from Antarctica.