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The Ādam Paradox Hypothesis 61
Why These Switches Support APH
These genomic switches support the APH for three reasons:
Their chronology predates ~70kya, ruling them out as late mutations.
They demonstrate preparedness, showing the genome was refined long
before the symbolic explosion.
Their dormancy matches the archaeological pattern: sparks without flame.
Only APH explains why continuity emerged suddenly after ~70kya. The
threshold of Adam represents activation, not invention.
FOXP2, HAR1, and SRGAP2C: The Switches that Turned Anatomy into
Symbolism
Why Random Convergence Doesn’t Work
The Synchrony Problem
For hundreds of thousands of years, humans with modern-looking brains left
almost no lasting symbols behind. Then suddenly, about 70–50 thousand years
ago, everything changed: we see engraved ochres at Blombos Cave (~77k years
ago), musical flutes, ornaments, and figurines in the early Upper Paleolithic
(~40–35k years ago).
This dramatic shift was not gradual. It looks like a phase transition — as
though several switches flipped together.
The genomic ignition of symbolic cognition was not the result of a single
master gene, but the convergence of many distinct loci and regulatory
switches acting in concert (see Figure 8.1: Symbolic Ignition Hierarchy).
Among the most discussed are:
FOXP2 — a regulatory gene shaping the neural circuits for speech, syntax,
and motor sequencing. A human-specific enhancer variant distinguishes its
function from Neanderthals, making it central to language readiness.
HAR1 — a noncoding RNA expressed in Cajal–Retzius neurons during
a narrow window of fetal development, crucial for cortical layering and the
folding patterns that define human brain architecture.
SRGAP2C — a human-specific duplication that slows synaptic pruning,
extending childhood plasticity and learning time, creating a prolonged
window for cultural and linguistic acquisition.