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1

Open the simulation

Navigate to https://jkh2.github.io/Primordial-Sim/ in any modern browser — Chrome, Firefox, Safari, or Edge. No install, no plugins, no build step required.The simulation starts immediately. A splash screen (hint card) displays the core controls. It dismisses automatically on your first interaction.
2

Choose a scenario preset

Open the World tab in the left panel and find the Scenario Presets dropdown. Six presets are available:Selecting a preset immediately resets the world with its tuned parameters. See Scenario Presets for a full breakdown of each.
3

Interact with the canvas

Click and right-click directly on the simulation canvas to shape the ecosystem in real time:
  • Left-click — Drop a cluster of 8 food pellets within a ~30px radius at the cursor position. Use this to rescue a starving population or attract organisms to a region.
  • Right-click — Spawn a group of 5 organisms of a random species at the cursor. Useful for reintroducing a species or seeding a new area.
  • Hover — Move the cursor over any organism to open an inspection tooltip showing its species, size, energy, age, kill count, and all four gene values.
4

Control time with keyboard shortcuts

Use your keyboard to manage simulation speed without touching the UI:
5

Read the UI panels

Two panels frame the canvas:Left panel — Simulation ControlsFive tabs let you tune every aspect of the world:
  • World — organism count, food settings, speed slider, real-time population graph, and species census
  • Species — species count, starting size, max size, organism speed, lifespan, reproduction thresholds, offspring count, and food oases
  • Rules — predation toggles (same-species protection, food chain mode), size advantage ratio, energy from eating, and the five behavioral drive sliders (Hunt, Flee, Flock, Food Attraction, Separation)
  • Evolve — enable/disable mutation, mutation rate and strength, and per-trait evolution toggles for Speed, Aggression, Efficiency, and Perception
  • Visual — additive glow, death particles, oasis indicators, food glow intensity, and trail length
The stats bar at the bottom of the left panel shows live FPS, Alive organism count, Food pellet count, and current Gen (generation).Right panel — AI Lab PartnerPress L or click the star icon (⚛) in the top-right corner to open the AI Lab. Configure your AI provider, then ask the assistant to analyze the ecosystem, design experiments, compare species, or write a full research report. See Controls & UI for full details.
Adaptive organism count on startup — the default starting organism count adjusts based on your device. On a large desktop display (over 1500px wide) it starts at 8,000. On a mid-range screen it starts at 5,000. On a narrower screen it starts at 3,000. On a touch device (coarse pointer) it starts at 2,000–4,000 depending on screen size. The simulation slider default is 5,000 and the food default is 2,000 with 5 species at speed 1.0x — but the adaptiveCount() function adjusts the initial organism count so the simulation runs smoothly regardless of hardware.

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Next steps

Controls & UI

Full reference for all mouse controls, keyboard shortcuts, panel tabs, stats bar, and the organism tooltip

Scenario Presets

Detailed breakdown of all six presets and when to use each one