Again the climate has seen much greater swings both up and down over the past 20,000 years in comparisome to recnt times,, while the very recent climate say the climate for the past 150 years has featured one of the most
stable climate intervals going back at least 20,000 years.
It appears that political fragmentation, sociopolitical instability and warfare occurred during the unstable
climate periods, while the growth of strong,
stable, successful states were favored during
stable climatic
intervals.