OT: Ecological Disaster and Global Politics

As an interesting aside that seems to somewhat related to all the discussion
of colonization, immigration, and "Pushes," I saw an interesting program on
U.S. Public Television (www.pbs.org) the other night. It was

called "Secrets of the Dead: Catastrophe!" And discussed a theory put forth by
an English scientist that a major eruption of Krakatoa in around 535 AD and
the ensuing ecological catastrophe played a major part in quite a few
upheavals in religion, politics, and populations, and that these changes

were both widespread and long lasting, still being felt today. It took them a
while to get to the point, and some of the conclusions are arguable (though
plausible), but overall it was quite fascinating. It also discusses
issues involving an asteroid strike and a tunguska-like comet airburst,
since in the beginning of his investigation, this scholar only theorized a
catastrophe, he wasn't sure exactly what kind until he further investigated
his theory. Altogether, if you're an astronomer, a vulcanologist, an
ecologist, a sociologist, an archaeologist, a historian, a meterologist, or
just plain insatiably curious, I highly recommend checking this program out.