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The Ādam Paradox Hypothesis 34
Strand Two: The Software — The Regulatory Genome and Neural
Connectivity
FOXP2: Tuning the Speech Circuits
FOXP2 mutations disrupt speech. In the famous KE family in Britain, carriers
of FOXP2 defects struggled with syntax and articulation (Lai et al., 2001). In
2002, Pääbo’s lab showed humans carry two unique amino acid substitutions
compared to chimps and Neanderthals (Enard et al., 2002).
Simon Fisher explained:
“FOXP2 is not a language gene per se. It is a transcription factor — a master switch that
regulates other genes involved in neural circuits for motor control and vocal learning.
”
(Fisher, 2017, p. 9)
Without such tuning, large brains could not coordinate the fine motor
sequencing of speech. FOXP2 represents software calibration of circuits, not
hardware mass.
HAR1: Wiring the Neocortex
HAR1, a non-coding RNA region, evolved 18 changes in humans compared to
chimps over just 6 million years — an astonishing acceleration (Pollard et al.,
2006). HAR1 regulates layering in the neocortex.
Pollard wrote:
“HAR1 is one of the most rapidly evolving sequences in the human genome. Its role in
cortical development makes it a prime candidate for shaping uniquely human cognition.
(Pollard et al., 2006, p. 162)
”
This was not a structural increase but a reprogramming of brain
connectivity.