> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/jkh2/Primordial-Sim/llms.txt
> Use this file to discover all available pages before exploring further.

# Species Settings

> Configure species count, sizing, lifespan, reproduction, and food oases.

The **Species** tab controls the initial conditions for each species population — how many species compete, how large they grow, how long they live, and where food concentrates in the world.

## Sliders

| Setting           | Range                | Default | Description                                                                                                                                                                              |
| ----------------- | -------------------- | ------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Number of Species | 2 – 12 (step 1)      | 5       | How many distinct species are created when the world initializes. Each species gets a unique color from the 12-color palette.                                                            |
| Starting Size     | 1.0 – 8.0 (step 0.5) | 3.0     | The size of every organism at birth. Size determines the initial energy pool since `size = sqrt(energy) × 1.5`.                                                                          |
| Max Size          | 8 – 40 (step 1)      | 18      | The upper size limit an organism can reach by eating. Organisms at max size can no longer grow but continue consuming energy.                                                            |
| Organism Speed    | 0.3 – 4.0 (step 0.1) | 1.2     | Base movement speed for all organisms. The Speed Gene can mutate this value up or down over generations.                                                                                 |
| Lifespan          | 10 – 120 s (step 5)  | 30      | Maximum age in seconds before an organism dies naturally. Shorter lifespans increase generational turnover and speed up evolution.                                                       |
| Reproduce at Size | 5 – 30 (step 1)      | 12      | Size threshold that triggers reproduction. When an organism's size reaches this value it spawns offspring at Starting Size, and its own energy is reduced to 40% (causing it to shrink). |
| Offspring Count   | 1 – 5 (step 1)       | 2       | Number of offspring produced per reproduction event. Higher counts grow populations quickly but also stress food supply.                                                                 |
| Food Oases        | 0 – 8 (step 1)       | 4       | Number of food-rich zones placed randomly in the world. Food spawn is biased 60% toward oases and 40% random.                                                                            |

<Warning>
  Changing **Number of Species** triggers `initWorld` and resets the entire simulation.
</Warning>

<Tip>
  Keep **Reproduce at Size** well below **Max Size** — if they are equal or close, organisms reproduce the instant they could grow further, preventing large predators from ever developing. A gap of at least 6 units (e.g., Reproduce at 12, Max at 18) allows a meaningful size hierarchy.
</Tip>

## Species color assignment

Species are assigned colors in index order from a fixed 12-color palette:

| Index | Name    | Hue  |
| ----- | ------- | ---- |
| 0     | Red     | 0.00 |
| 1     | Orange  | 0.08 |
| 2     | Gold    | 0.15 |
| 3     | Green   | 0.30 |
| 4     | Teal    | 0.45 |
| 5     | Cyan    | 0.55 |
| 6     | Blue    | 0.65 |
| 7     | Indigo  | 0.75 |
| 8     | Purple  | 0.83 |
| 9     | Magenta | 0.92 |
| 10    | Lime    | 0.18 |
| 11    | Emerald | 0.38 |

Hue values are passed directly to the GLSL `hsv()` function in the particle fragment shader.

## Size–energy relationship

An organism's rendered size is derived from its internal energy value:

```text theme={null}
size = sqrt(energy) × 1.5
```

This means energy scales with the square of size — a larger organism needs proportionally more food to maintain its size and to grow further. This relationship naturally limits unchecked growth and creates ecological pressure.

## Food oases mechanics

Each oasis is placed at a random position within the canvas with a radius between 80 and 200 px (`80 + random() × 120`). A random strength value between 2 and 5 is also assigned per oasis.

When a food pellet spawns:

* **60%** of the time it is placed within or near an oasis (biased toward that oasis center)
* **40%** of the time it is placed at a uniformly random canvas location

With **Show Food Oases** enabled in the Visual tab, semi-transparent teal circles mark each zone.