Code and data associated with "The evolution of sex for artificial intelligence - A population-genetic framework for multigenerational model populations". Gilestro, 2026
Find a file
Giorgio Gilestro 287d2326cc epistasis_predicts: functional conflict, not weight geometry, predicts merge failure pre-merge
The decisive experiment from the external review. 39 LoRA parent pairs
(0.5B, 3 seeds) on three axes decorrelated by construction: conflict
(contradictory conventions on shared prompts, private budgets fixed),
compat (same prompts, SAME convention — overlap without conflict), and
duration (weight divergence, zero conflict). Six pre-merge predictors;
primary outcome = merge penalty (parent potential − merged achieved).

League table (Spearman vs penalty, n=39): functional measures predict
(dis_raw +0.460, epi_conf +0.446, p<0.005); geometry collapses
(delta_cos +0.03, delta_l2 +0.17 n.s.); gradient alignment weak (−0.35);
performance ~0. The first grid's apparent geometry win (+0.60) was an
overlap/volume artifact — the compat control axis (added for exactly
this) exposed and killed it: same overlap and data volume, zero penalty.
Honest riders in the README: confidence weighting does not beat raw
disagreement as a rank predictor (pre-registered internal prediction not
confirmed; it does double the conflict/compat level contrast), and
|rho|~0.45 is bounded by 0.5B merge-outcome noise (7B is the firm-up).

Also: micro-batched gradient accumulation (OOM fix on the shared 16GB
GPU), exact r-space LoRA-delta geometry (brute-force-verified test,
151 green), systemd-run runbook lesson (tmux dies with the SSH session
scope on this box).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BkRLcc18rwT2Lysu6PbG7v
2026-09-06 17:19:46 +01:00
configs epistasis_predicts: functional conflict, not weight geometry, predicts merge failure pre-merge 2026-09-06 17:19:46 +01:00
figures epistasis_predicts: functional conflict, not weight geometry, predicts merge failure pre-merge 2026-09-06 17:19:46 +01:00
hpc hard benchmark: the 7B "fusion wins / no headroom" results were saturation artefacts 2026-07-05 19:13:26 +01:00
paper paper: claim-narrowing revision from the external review 2026-09-06 15:14:28 +01:00
results epistasis_predicts: functional conflict, not weight geometry, predicts merge failure pre-merge 2026-09-06 17:19:46 +01:00
src epistasis_predicts: functional conflict, not weight geometry, predicts merge failure pre-merge 2026-09-06 17:19:46 +01:00
tasks epistasis_predicts: functional conflict, not weight geometry, predicts merge failure pre-merge 2026-09-06 17:19:46 +01:00
tests epistasis_predicts: functional conflict, not weight geometry, predicts merge failure pre-merge 2026-09-06 17:19:46 +01:00
.gitignore neural: real-MNIST external-validity tier (collapse + grounding) 2026-07-05 09:19:36 +01:00
CLAUDE.md hard benchmark: the 7B "fusion wins / no headroom" results were saturation artefacts 2026-07-05 19:13:26 +01:00
Makefile Phase 3: LLM-tier speciation + multi-seed firm-up of the recombination claims 2026-09-06 15:39:15 +01:00
pyproject.toml llm: first real-LLM prototype — recombining specialist LLMs (C2/C4) 2026-07-05 15:48:02 +01:00
README.md paper: reframe the perspective paper around sexual reproduction (v4 -> v5) 2026-07-05 13:53:10 +01:00
uv.lock Layer 1.5: architecture-general neural existence proof 2026-07-04 21:02:49 +01:00

The Lamarckian Society — Layer 1 (analytical core)

A parametric population-genetics model of knowledge transmission across generations of learning agents. Knowledge transmission is modelled literally as a WrightFisher process (not by analogy): a model's knowledge is a distribution p_t over K discrete items; a fixed true distribution p* has a rare tail; each generational step is "sample from the parent (drift) + mix in fresh real samples (grounding/immigration) + refit." Model collapse is the loss of rare alleles under drift.

See paper/blueprint.md (the normative build spec), paper/the-lamarckian-society-v5.md (the perspective paper), and paper/results-summary.md (a summary of all results).

Reproduce

Environment is a uv venv built from the committed, hash-pinned uv.lock — that lockfile is the single source of truth for "it runs" (Layer 1 is pure NumPy/SciPy and bitwise-reproducible from a seed; no container needed).

# one-time: install uv (https://astral.sh/uv)
curl -LsSf https://astral.sh/uv/install.sh | sh

uv sync                 # build .venv from uv.lock
make test               # correctness + scientific-validation tests (the spine of trust)
make layer1             # run experiments E1E6
make figures            # regenerate figures from committed results

Layout

src/knowledge/   Layer 1 package (imported as `knowledge`)
configs/layer1/  one YAML per experiment (E1..E6)
figures/         plot_EX.py — read results.parquet only
tests/           test_correctness.py + test_scientific_validation.py (analytic checks)
paper/           blueprint.md, perspective paper, figure_manifest.md
results/         written artifacts (gitignored; hashes tracked in manifest.json)