Every organism carries a heritable genome of seven genes. Organisms sense nearby food, threats and mates, choose a behavior, burn energy moving, eat, and — if they store enough energy — find a mate and reproduce. Offspring inherit a per-gene mix of both parents plus mutation. Nothing is scripted: population curves and trait drift emerge from local rules only.
size 0.6–1.8 — bigger bodies store more energy and win fights, but cost ~size1.4 to run.speed 0.6–1.8 — faster travel and escapes; movement cost scales with speed².sense 0.6–1.8 — detection radius for food, mates and threats. Larger head/eyes.camo 0–1 — blends color toward the terrain; shrinks the range at which predators spot you.nocturnal 0–1 — shifts the activity / vision curve toward night.fertility 0.7–1.4 — lowers the energy bar for mating and raises twin chance.hue 0–1 — cosmetic tint, lets you watch lineages visually.Genes are visible on the body: size scales the whole animal, speed stretches
the torso and lengthens legs (and a stalker's tail), sense grows the head — a glimmer's
ears, a skitter's eye stalks, a stalker's snout — and camo/hue/nocturnal
set the coloring. Each species has its own body plan: round grazers with tall ears and a puff tail,
low six-legged scavengers with eye stalks and a beak, and lean spike-backed predators with a long snout.
A utility state machine per organism: flee beats everything (threat inside detection range, reduced by the prey's camo and by darkness for diurnal hunters); then hunt/forage when hungry; then seek mate when energy > mating threshold; otherwise wander. When the activity curve says it's the wrong time of day, organisms sleep: cheap, but they sense poorly — sleeping prey is easy prey.
Mating costs both parents energy, which becomes the child's starting energy. Each gene is taken from a random parent, then mutated with gaussian noise of σ = 7% of the gene range, with an 8% chance of a large (3σ) jump — those get flagged as ⚡ mutants in the event log. Generation = max(parents)+1.
The sun orbits on a 80-second day. Consequences: plants photosynthesize only in light; vision
ranges scale with the match between an organism's nocturnal gene and the darkness;
mismatched organisms fall asleep and become vulnerable. Watch for night-hunting stalker lineages.
Everything derives from the seed in the toolbar: terrain (fractal value noise × radial falloff), plant distribution (moisture noise), starting populations and per-island jitter of species base traits. Restart replays the same island; 🎲 rolls a new one.
All organisms, plants, rocks and carrion are GPU-instanced (a handful of draw calls). Neighbor queries use a spatial hash grid. The simulation runs on a fixed 1/30 s timestep scaled by the speed slider, capped per frame so the tab never spirals. Populations are hard-capped (420 / 240 / 48).