A chimpanzee society simulation, based on wild chimps.

Outside the app, test runs hand the same chimps to other deciders: trained adapters, the stand-ins that imitate them in long runs, Jev, and rules that keep their plan.

1. observe()

   A private snapshot of what this chimp sees, hears, feels and remembers. Nothing it couldn't know.

2. Legal options

   Up to 8 moves that are possible right now, each written as a plain sentence, always including the rules' pick.

3. GLiNER scores

   The model scores every option against the snapshot, in about 0.4 s.

4. Check

   The server validates the answer; the simulation re-checks the move is still legal.

5. Act and trace

   The chimp acts. The trace keeps every score and what the rules would have picked.

What the model actually read418 tokens · 478 ms

meTavuni, adult male, 27 y, West community; the alpha, rank 1 of 8 males; mood calm; timid; solitary; playful

feelingmild hunger

now07:19 dawn; thunderstorm, 16 °C; party of 5 with 2 adult males

nearbySanaki: my ally, adult male, ranks below me, 2 m, close bond · Yerubi: juvenile female, 2 m · 2 more

memoriesJust now: a heavy storm broke

eventsA heavy thunderstorm is pouring down

“You are a field primatologist. Choose what this wild eastern chimpanzee would most plausibly do next, given only what it perceives, feels and remembers…”

1. Sit hunched through the storm AI pick rules pick57%
2. Groom my ally Sanaki to keep his support17%
3. Groom Yerubi, juvenile7%
4. Play with the young Yerubi6%
5. Sit and rest nearby4%
6. Forage on leaves and pith nearby4%
7. Charging display to assert my alpha status3%
8. Travel toward Rukaso's pant-hoots3%

• Rank and alphas

  Males rise by winning contests, scored with Elo ratings (Neumann et al. 2011), and lower-ranked chimps greet higher ones with a pant-grunt, a breathy "you're the boss". The alpha usually falls to a rival with friends. Females queue by age and tenure instead (Foerster et al. 2016).

• Alliances

  Chimps who groom each other, back each other up and share meat become allies. When a friend gets charged, allies may jump in, and that's how a smaller male can topple a stronger one.

• Fights and making up

  Most conflicts are charges and bluffs; about 1 in 20 gets physical. Afterwards, rivals often reconcile and friends console the loser (Kutsukake & Castles 2004). A fight that never gets patched up leaves tension that fades over a few weeks, modeled on how chimps' relationships vary in value and compatibility (Fraser, Schino & Aureli 2008).

• Territories and patrols

  Every week or two, a group of males patrols the border in silence (Watts & Mitani 2001). Meeting strangers, they count heads: outnumber them and they charge; outnumbered, they slip quietly home. Most encounters are only heard, not seen (Wilson et al. 2012).

• Hunting and sharing

  When several males spot red colobus monkeys, a hunt can start. More hunters, better odds, as at Ngogo (Mitani & Watts 1999). The catch gets shared with friends, allies and family who beg.

• Babies and families

  A baby rides on mom's belly, then her back, and nurses until 4 or 5. The next one comes about five years after the last (Wallis 1997). Death rates by age follow Ngogo's (Wood et al. 2017), and orphans are sometimes adopted by an older sibling.

• Females change communities

  Around age 12, most young females move to a neighboring community and start at the bottom of the female pecking order. Males stay home for life.

• Food and weather

  A community splits into parties, temporary subgroups that merge and split all day: big ones at a fig feast, small ones when fruit is scarce. Storms send everyone to shelter.

• Stranger call playback

  A hidden speaker plays a strange male's pant-hoot. Do they go look, call back or sneak away? (Wilson, Hauser & Wrangham 2001)

• Snake model

  A fake viper on the trail. Who spots it, and do they warn the ones who haven't? (Crockford et al. 2012)

• Fig feast

  A giant fig ripens all at once. Watch everyone show up.

• Storm

  A heavy downpour, right now. Everyone hunkers down; a few males do a rain display.

• Drought

  A few days with hardly any fruit. Parties shrink and squabbles over food go up.

• Remove the alpha

  The boss vanishes. Watch the struggle to fill the top spot.

• Monkeys arrive

  A group of red colobus moves in overhead. Hunting chance. (Watts & Mitani 2002)

• Before and after

  The Mind tab puts the chimp's choice right before the experiment next to the one right after.

Made with TypeScript, three.js for the 3D, Web Audio for sound, and SQLite running in the browser for saves.

• Rules

  The built-in recipe that runs the app. It was tuned on travel share, party size and day range, which gives it a home advantage. Even so, in the free test its chimps travel too much, groom too little and walk too far each day.

• Untuned GLiNER2.5-Decide

  The model as downloaded. It leans social: over three observed days its chimps groomed 28% of daylight (wild: 8–18%) and walked 0.15 km a day (wild: 1.5–3.5 km). When aggression was on offer it chose it about five times as often as the field-expert labels (0.29 against 0.06).

• Trained adapters

  Three small add-ons to GLiNER (LoRA adapters), trained on the same 900 decisions with different labels: a field-expert baseline, an aggressive temperament and a collaborative one. The labels come from an AI labeller following a written rubric, not from field data. On 200 held-out decisions, each adapter matches its own labels far better than the untuned model (0.74, 0.72 and 0.81 against 0.40–0.54), and the temperaments separate clearly.

• Jev (TypeSafe System One)

  A hosted model that turns a described situation and a set of options into probabilities. Driving one community at a time for three days, it chose less aggression and more grooming than rules, and picked social options 64% of the time when they were offered (expert labels: 36%). A paid decisive test is approved but hasn't run.

• Rules + plan

  The same rules with two changes. A chimp keeps its current plan until something important changes, such as a need crossing a threshold, the time of day moving on, an interruption, the plan ending, or 90 minutes passing. And it picks from the rules' scores with some randomness instead of always taking the top one. In the free test this cut the gap to wild chimps by 55%, on all five worlds.

• Two controls: a formula and random choice

  The utility formula scores each option by how much hunger, thirst, tiredness and loneliness it relieves per hour, walk included, using the simulation's own rates. No model is involved. Random choice picks any legal option. Random choice beat rules on distance, but its chimps went hungry, so it doesn't count.

• The paid Jev test. Approved with a hard $10 cap, not run yet: it waits for a spending guard tested against a fake server. Jev counts as helping only if its version with facts and randomness beats rules by at least 0.10 on average and on 4 of 5 worlds, beats both rules + plan and the utility formula by at least 0.05 on 4 of 5 worlds, and keeps its chimps fed.
• Rules + plan as the default policy. Approved and pre-registered as stage C13. It can be switched off, and the combined proof run will judge it. That run hasn't happened yet.
• Long runs of the trained adapters. The five-year numbers come from stand-ins: small networks fitted to imitate each adapter, which agree with it on 67–77% of decisions in worlds they never saw. They are not the adapters themselves.