Page 244 - Flipping book The Adam Paradox Hypothesis - Second Edition.pdf

The Ādam Paradox Hypothesis 221
Where the Model Breaks
But closer inspection reveals fatal flaws.
1. The Missing Bridge
If culture alone explains ignition, symbolic artifacts should appear continuously
across the last 300,000 years. But they do not. Instead, traditions appear briefly,
vanish, and leave long gaps.
Ochre appears, then disappears.
Shell ornaments appear, then vanish.
No stable cumulative culture emerges until after ~70kya.
This is not a ratchet. It is a loose gear that keeps slipping back.
2. The Ratchet Paradox
The ratchet requires a stable symbolic baseline. But where did that baseline
come from?
Teaching and imitation can amplify an existing system.
But they cannot create the first system out of nothing.
Without shared symbols, knowledge transmission collapses under noise and
forgetfulness.
Mathematically, cultural transmission below a critical fidelity threshold leads
to extinction bias: traditions die out faster than they accumulate (Boyd &
Richerson, 1985). The pre-70kya record looks exactly like this: sparks that
extinguish before they can ignite.
This comes from Boyd & Richerson’s (1985) models of cultural evolution,
which use mathematics similar to population genetics. Let’s break it down:
The Core Idea
Cultural traits (stories, rituals, tool-making methods) spread only if they are
copied with enough fidelity (accuracy in transmission). If copying errors
accumulate too fast, traditions decay faster than they grow. This is called the
critical fidelity threshold.
Above threshold → culture stabilizes and accumulates.
Below threshold → culture decays and disappears.