on the world Economy since the dawn of Industrialization. An explosion of agriculture and population in Africa that followed the Arctic Sea Ice extent rate would be staggering. At the same time we'd likely see effects as well on transmission of disease as new vectors teleconnect currently isolated regions. The odds remain low that this is the case. Likelier, green transients will collapse or continue to shift and drift without much permanent impact. It's why desert nomads have been nomadic. If I misunderstood what you're saying, it appears that makes both of us. Nothing in what you yodaspoke added to the understanding of the issue. The dairying article from Nature asserted a green Sahara that need have been no more green than it is today for its thesis or its evidence to be true. That lack of parsimony calls into question the balance of its Scientific approach, though its main conclusions might be valid. And what is this obsession with prehistoric things? Do you wish you were a caveman? Do you long nostalgically for a simpler era? The dairying article from Nature asserted a green Sahara that need have been no more green than it is today for its thesis or its evidence to be true. I thought we were talking about something widely known. As easy as Wikipedia: -- The Neolithic Subpluvial -- sometimes called the Holocene Wet Phase -- was an extended period (from about 7500-7000 BCE to about 3500-3000 BCE) of wet and rainy conditions in the