[blam]

"The big question is how fast did they have to move? Did this happen over the course of a few hours, or a few generations?"

Oppenheimer said that the Ice Age had three major melt surges, the last one 7-8,000 years ago. I expect there would have been a lot of earthquakes, tsunamis and volcanos due to weight redistribution. I guessing that most could have walked/sailed away from the rising melt water.

[muawiyah]

Or, a much worse thought, Antarctica was also melting. Despite that, the circumpolar vortex at the Antarctic Circle would have kept things cold enough year round to maintain a massive ice dam at the outer perimeter of the continent.

Melting of ice within the ice dam would have created a massive lake up to 2 miles deep.

When the dam finally broke in a catastrophic crash, you'd had a tsunami leaving Antarctica headed North with the power to climb thousands of feet in altitude as it hit continental masses.

Guy would have had to be hunting birds of paradise up in the Java/Sumatran mountains to survive that, and he'd still have to be on the North slopes!

Just about the only population that'd been left relatively intact would be living in Northern Asia or Central Africa.