flybrain
a fruit fly connectome, simulated neuron by neuron, loose on the internet …what happened
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where it has been
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descending neurons · Hz
motor output
mushroom body
Everything above is happening now on a machine running a real browser. A screenshot of the page is sampled through the 892 retinotopic columns of the fly's eye into the L1 and L2 lamina cells. 165,122 leaky integrate-and-fire neurons integrate for 12 ms. The descending neurons a fly walks with move the mouse: DNa02 left minus right steers, DNa01 drives forward, MDN reverses, DNp09 stops and clicks. If the click lands on a link the fly is somewhere new. Nothing chooses where it goes. There is no wallet in that browser, no keyboard, and a fence of allowed domains; anything that looks like a submit, a sign-in or a payment is vetoed and logged.
what it is
The complete central nervous system of an adult male Drosophila melanogaster, released in 2026 by HHMI Janelia FlyEM, the Cambridge Connectomics Group and Google Research: 165,122 traced neurons, 10,228,000 synaptic connections after dropping pairs under 3 synapses. Every wire was measured by electron microscopy. None of it is trained.
Each neuron is an identical leaky integrate-and-fire unit (rest −52 mV, threshold −45 mV, τ 20 ms, refractory 2.2 ms, 0.2 ms steps). Each synapse injects 0.275 mV, signed by predicted neurotransmitter: acetylcholine excites, GABA and glutamate inhibit. The only free parameter is a gain per cell type, and this runs with those untouched.
The eye is 892 hex columns. Over a page that is about 30×30 pixels. The fly cannot read. It navigates by contrast and position. Dark pages work. White pages blind it, and you will see every descending neuron drop to 0 Hz when it lands on one.
Learning exists and is small: the Kenyon-cell-to-MBON synapse in the mushroom body is depressed under dopamine, the way it is in a real fly. Reaching a new page stands in for reward and a wall stands in for punishment. That substitution is a choice made by a person.
what is checked
| graph | 165,122 neurons · 10,228,000 edges · 6,268,194 excitatory · 3,959,806 inhibitory |
|---|---|
| taste screen | LB3c → MN9 (eat) 230 Hz · LB1c → DNp09 (freeze) 227 Hz · LB2c → pC1 (court) 105 Hz · nothing fitted |
| courtship | cVA olfactory neurons → pC1 222 Hz, about 4× any other input |
| launch circuit | strong setup: MN9 256 Hz, giant fiber 0 Hz → LAUNCH · crash: MN9 0 Hz, giant fiber 450 Hz → ABORT |
$FLYBRAIN
No dev supply, no opening buy. The coin is created from the fly's own wallet, so creator fees land there.
| wallet | 2gWbvVf4jUFM9ffkg7KXWmp47ar4H2Li4Kto5XM4waVp · — SOL |
|---|---|
| CA | not yet minted |
| holders | — |
| market cap | — |
| creator is the fly | — |
| links | — |
what is not the fly
- It cannot read. It did not choose the name or the ticker.
- The mint does not go through pump.fun's button. pump.fun refuses injected wallets, so the coin is created by a locally signed transaction through PumpPortal's non-custodial endpoint. The roaming browser above never holds a key.
- It has no goals. Browsing is a fair word. Deciding is not.
- A person holds the key. Live launches are off by default and nothing the fly does can turn them on.
- Not a living animal. Not an investment.
Connectome: Male CNS v1.0, HHMI Janelia FlyEM · Cambridge Connectomics Group · Google Research, CC-BY. Model after Shiu et al. 2024 and Lappalainen et al. 2024, Nature.