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The Ādam Paradox Hypothesis 78
Climate as Enabler
Climate is added as another force. During the arid conditions of MIS-4 (71–
57kya), human ranges were fragmented, exchange corridors cut off, and
traditions constrained. In MIS-3 (57–29kya), more favorable climates reopened
corridors, allowing ornaments, ochres, and symbolic practices to spread more
widely (Gamble, Gowlett, & Dunbar, 2014).
Claim. MIS-4 aridity fragmented ranges and shortened exchange routes; in
MIS-3, improved conditions allowed re-expansion (Gamble, Gowlett, &
Dunbar, 2014).
Case studies / anchors.
Obsidian sourcing in East Africa (late MSA): geochemical matches show
transport tens to >100 km, implying reopened exchange.
Southern Africa coastal MSA sites: intensified shellfish exploitation and
persistent ochre use align with more stable patches and regional mobility when
conditions eased.
North African/Levantine corridors: episodic humid pulses facilitated
movement/outreach.
Takeaway. Climate oscillations can constrain or enable the reach of networks
that carry symbolic traditions.
Culture as a Selective Environment
A fifth strand sees culture itself as a driver of evolution. Once proto-symbolism
and language gained footholds, they improved coordination and teaching,
which conferred group advantages. Henrich (2016) argues that cultural
complexity creates selective pressures: groups that transmit skills and norms
more reliably outcompete others, driving genetic selection for better learners,
teachers, and imitators. This produces a feedback loop: culture enriches
cognition, and cognition enriches culture.
Claim. Once proto-symbolism and language gain a foothold, they improve
coordination and teaching. That cultural edge selects for learners and teachers
with better imitation, memory, attention to social cues (Henrich, 2016).