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The Ādam Paradox Hypothesis 42
Tattersall framed it:
“It may be that Homo sapiens survived by the narrowest of margins.
Such crises are filters, reducing numbers but focusing lineages, setting the
stage for change.
” (Tattersall, 2012, p. 177)
Table 6.1 — Bottlenecks in Human Evolution
Takeaway: Humanity nearly vanished. Survivors carried a
pruned, refined genome.
Strand Two: Climate Windows — Ice Age Cycles and
Refugia
“The Toba super-
eruption may have
plunged early Homo
sapiens into near-
extinction, creating a
genetic bottleneck that
shaped modern
diversity.
” (Ambrose,
1998, p. 623)
The Harshness of MIS 6 and 4
Marine Isotope Stage (MIS) 6 (~190–130 ka) and MIS 4
(~71–57 ka) were brutal glacial periods. Africa experienced
extreme aridity, shrinking habitable zones. Chris Stringer
noted:
“During MIS 6, much of Africa was uninhabitable desert. Human
populations likely survived only in scattered refugia.
” (Stringer, 2016,
p. 121)
Likewise, MIS 4 was marked by aridification across Africa and
Arabia, forcing humans into coastal refugia such as southern
Africa.
