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The Ādam Paradox Hypothesis 39
Part II — Preparing the Vessel: Readiness Before Ignition
Chapter 6
Climate Windows, Bottlenecks, and Roads Out
How bottlenecks, Ice Age cycles, and dispersals set evolutionary pressure on the
genome.
Introduction: Evolution Under Pressure
Evolution is not just about genes. It is about genes under pressure — refined
in crucibles of survival. The history of Homo sapiens unfolded against a
backdrop of Ice Age cycles, harsh bottlenecks, and fragile survival in isolated
refugia.
Genetic studies show our species nearly disappeared multiple times.
Paleoenvironmental records reveal narrow
“
windows”
when climates allowed
dispersal, and others when environments trapped humans in marginal zones.
Archaeology traces the roads out of Africa, timed precisely with symbolic
breakthroughs.
This chapter follows three strands:
1.Bottlenecks — The Narrowing of the Species
2.Climate Windows — Ice Age Cycles and Refugia
3.Roads Out — The Migrations That Carried Symbols