What is this?
A small glass world with eleven species in it: a fly, ants, moths, fireflies, crickets, snails, bees, water striders, minnows, a frog and a spider. Thirty animals in all.
No script tells those eleven where to go. Each one is a small network of simulated spiking neurons, the leaky integrate-and-fire kind (LIF). It is the same neuron family, with the same settings (rest -52 mV, threshold -45 mV, 20 ms time constant), used in the 2024 whole-brain fruit fly model. Senses push current into the neurons, the neurons spike, and the spikes turn the legs. That is all.
Two real brains, labelled honestly.
- Fruit fly (FlyWire): 467 real neurons and 22,285 real synapses from the adult fly brain: the sugar-taste to feeding pathway. It runs the published model's own rule, step for step, and reproduces the published sugar experiment (the feeding motor neuron MN9 fires about 115 times a second when its sugar neurons are stimulated; reference 113). When a fruit fly stands on fruit or a flower, its sugar neurons fire, and it eats only when MN9 actually fires. This circuit has no walking neurons, so it walks on a simple rule and eats on its real brain.
- Worm (C. elegans): all 302 real neurons on the real wiring map, run as graded (non-spiking) neurons, as most real worm neurons are. It passes the classic touch test: touch its head (tap next to it, or let another animal bump it) and its backward command cells win and it backs away; touch its tail and it hurries forward; when its nose (the ASH pain cells) meets a wall or the pond, it reverses. That result depends on one sign rule from the literature (Wicks & Rankin): with plain signs the reflex runs backwards. Its crawling, steering, food-finding and eating are simple rules. Real wiring, touch reflex validated (Wicks & Rankin sign rule); chemotaxis and crawling rhythm not validated.
- When these animals have young, small mutations change their brains. The label says how far a brain has drifted from the original (for example "brain 3.2% changed from the validated FlyWire circuit"). Sensor and motor neurons never mutate.
- Ants carry crumbs home and lay trails the others follow.
- Fireflies see each other flash and drift into sync.
- A cricket sings at dusk and the other one walks toward the song.
- Snails pull into their shells when touched. The frog only notices small moving specks.
- Moths find the lamp at night. The whole place runs on your real clock.
Nothing here can be hurt. Nothing eats anything alive. The only things you can do are feed, seed, touch and watch.
Runs entirely in your browser, offline. If your browser allows it, the animals are remembered on this device between visits (the world pauses while the page is closed).
Fly circuit: FlyWire v783 connectome (Dorkenwald et al. 2024, Schlegel et al. 2024), model after Shiu et al., Nature 2024. CC BY-NC 4.0, non-commercial.
C. elegans wiring: Cook et al., Nature 2019; graded neuron model after Kunert et al. 2014; touch sign rule after Wicks & Rankin. The Cook 2019 connectome data is NOT Creative Commons: non-commercial research and education use only; permission from the authors is pending before any wider release.