An interactive browser-based artificial ecosystem where creatures with genetic traits evolve, compete, and thrive in a virtual Petri dish.
Petri simulates a microscopic world where digital organisms:
- Eat — seek food within their sense radius
- Hunt — aggressive creatures chase and consume smaller ones
- Flee — prey creatures detect and escape predators
- Reproduce — split via mitosis when energy is high enough, passing genes with mutations
- Evolve — natural selection favors the fittest, driving emergent evolution
- Die — when energy runs out, they're gone
No two simulations are alike. Watch species emerge, compete, and sometimes go extinct — then see life find a way again.
Each creature carries a genome with 7 traits:
| Gene | Range | Effect |
|---|---|---|
| Speed | 0.5–5.0 | Movement speed (higher = faster but more energy) |
| Size | 3–20px | Body size (bigger = can eat smaller, but costs more) |
| Sense Radius | 20–150px | Detection range for food and threats |
| Hue | 0–360° | Color (visual species identification) |
| Metabolism | 0.5–2.0 | Energy efficiency (lower = more efficient) |
| Aggression | 0–1 | Predator tendency (>0.5 = will hunt smaller creatures) |
| Reproduction Threshold | 60–150 | Energy needed to reproduce |
- Play/Pause — stop/start the simulation
- Speed — 1×, 2×, or 5× simulation speed
- Food Spawn Rate — how fast food appears
- Mutation Rate — how often offspring genes change
- Mutation Strength — how much genes can change per mutation
- Friction — world drag (lower = creatures slide more)
- Food Burst — spawn 50 food items instantly
- Add Creature — introduce a new random creature
- Reset — start over with fresh creatures and food
- Click a creature — inspect its genome and stats
- TypeScript + Vite
- HTML5 Canvas (custom rendering engine)
- Chart.js (population graphs)
- Zero frameworks — pure simulation
git clone https://github.com/loicgasser/petri.git
cd petri
npm install
npm run devThen open http://localhost:3000
npm run buildStatic site outputs to dist/.
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