Metabolism M2.7: one species, many minds — strains (song-compiled LittleVMs), bodies with fixed allegiance, living wells, food-limited economy

metabolism/EVOLUTION.md

@@ -129,62 +129,53 @@ within-seed ≈ 0.02–0.04, ~4–7×) even though the films look different. Bro
 the instruction grammar (more branch shapes, richer memory, more action
 archetypes) is the natural next step for this layer.
 
-### M2.7 — one species, many minds: strains & allegiances (design agreed; not yet built)
+### M2.7 — one species, many minds: strains & allegiances ✔
 
-A further correction, agreed before building anything on M2.6: **drop tribes
-entirely.** Not three castes, not k tribes of fixed membership. The picture is
-*one population of specialised microorganisms building a bigger organism* —
-and then several such macro-organisms sharing a map, sometimes fighting,
-sometimes cooperating. Membership is a property of each organism, and it can
-change over time.
+Built — with one correction agreed mid-build, after watching the first films:
 
-**Wells keep the correction from the previous draft** — small, weak, many
-(8–16), born where a pitch class enters and holds, drifting with its harmony,
-dying when it leaves, all on a precompiled deterministic timeline — because
-wells are where bodies collide: everyone needs them, so a well is the natural
-front, its birth a land-rush, its death a retreat.
+> **Allegiance does not change sides.** The original draft had fronts
+> converting, collapsed bodies leaking their members, splinters seceding and
+> friendly bodies merging. On screen that read as one thing: every colour
+> blurring into every other within a minute — ugly, and it erased the very
+> polities the mechanic was meant to create. So the fluid politics were
+> removed: bodies are founded once and persist; war kills, it does not
+> convert; there is no defection and no merger. What keeps the cast plural is
+> **colonisation** — a blessed settlement on virgin ground, far from every
+> body core, plants a new flag. And the renderer now paints each cell in its
+> DOMINANT body's colour, so territories read as territories.
 
-**The population is one density field with two live properties:**
+What was built:
 
-- **strain mix (personality).** The song decides how many minds it needs —
-  *m* strains from the number of independent voices the mix resolves into,
-  bounded by arrangement depth, jittered by the seed — and compiles a
-  **LittleVM program per strain** from the grammar: senses (food, density,
-  trail, law, hunger, rim, well proximity and liveliness, body presence),
-  registers as memory, real branching, actions (move, graze, excrete, hit,
-  spawn, follow, patrol). Density is partitioned by strain; each strain
-  advects by its own program. And the mix **evolves by local selection**:
-  strains that eat and grow where they stand propagate, proportions shift
-  district by district — specialisation is visible and develops over the film.
-- **allegiance (the body).** A composition field over bodies (the song opens
-  2–4; a cap of ~8 keeps colour legible), advected frozen-in with the
-  population flux. Same body = **cooperation**: shared trails, reinforcement,
-  complementary strains building one structure. Different bodies = **contest**
-  where presences overlap: hit-actions spend density to push the other body's
-  ground and convert it, scaled by the song's harmony — consonant, locked
-  voices breed truce and symbiosis; dissonant, decorrelated voices breed
-  skirmish and siege. Allegiance changes by rule, never by fiat:
-  - **conversion** — a won front converts the locals it overruns;
-  - **defection** — a body whose presence collapses (starved, outflanked)
-    releases its members to the neighbouring body;
-  - **fission** — a coherent splinter cut off from its body, hit by a strong
-    onset, founds a new body with a new colour;
-  - **merger** — two bodies whose members fully intermix under a cooperative
-    regime become one.
+- **strains** (`src/song/strains.js`) — the song decides how many minds it
+  needs (2–5, from onset density, an independent spectral voice, texture
+  noisiness, seed jitter) and compiles a LittleVM program per strain from
+  motif roles: builder, grazer, scout, sentinel, breeder. Senses include the
+  body's presence (KIN/FOE), the living wells, and the section's PEACE — a
+  program can branch on war or truce. The world runs local selection:
+  strains that thrive where they stand propagate.
+- **living wells** (`src/sim/wells.js`) — a precompiled deterministic
+  timeline of small, weak, numerous wells (4+ at open, ≤12 alive): born where
+  a pitch class enters and holds, drifting along its harmony's compass,
+  starving when it leaves. A birth is a land-rush; a death a retreat.
+- **bodies & diplomacy** — allegiance is a concentration field advected
+  frozen-in with the population flux (Σ bodies = density exactly, a test).
+  Diplomacy = the track's consonance bent by the section's peace operator;
+  hostile fronts bleed the loser (casualties, never conversion). Colonisation
+  plants new bodies on blessed virgin ground.
+- **a food-limited economy** — the old world was accidentally
+  cap-limited: the gate floor let life grow on bare ground, so the dish
+  filled to a uniform saturated carpet and stopped moving. Now the gate is
+  nearly shut without food and starvation dissolves colonies off bare
+  ground: the population tracks its wells, blooms on them, and must keep
+  moving to keep eating.
 
-**The song sets the diplomacy.** Consonance and the section regimes map to
-war and peace: drops are expansion wars, breakdowns are truces and mutual
-building, an outro is a settling of borders. The body-to-body relations come
-from the music, not a constant.
-
-*Exit: two songs with the same pulse but different arrangement depth compile
-different strain counts and different diplomacies; at least one allegiance
-change (conversion, defection, fission or merger) is legible on screen per
-film; strain proportions measurably drift across the film (local selection
-actually runs); a well's birth, drift and death are each legible; the world's
-typed-array layers, trail tints and palette generalise from 3 fixed castes to
-the strain/body fields; the prepared-artifact path still rebuilds
-bit-identical timelines, programs and opening state.*
+*Outcome:* 39 tests green, including the allegiance invariant (no negatives,
+composition = population), war-kills-not-converts (a war world ends poorer
+than its truce twin, with each body's mass still in its own heartland),
+colonisation, strain-mix drift, well determinism/drift/land-rush. Realtime
+holds at 640×360 (~12 ms/frame sim+render). Songs still diverge ≫ seeds on
+the fingerprint (classMix now sorted — the seed permutes the casting, the
+song decides its shape).
 
 ### M3 — the lens: travel, don't cut
 Replace the cut-to-a-point grammar with a **move grammar**: *track* (follow a