A real fly brain, flying the real world.
Fruit Fly Airlines is a free browser game and science toy. You fly a glass fruit fly, with all 165,122 neurons of a real fruit fly's nervous system inside it, through 166 cities around the world, each in its real local time and live weather. Or you hand the controls to the fly's own brain, and find out which city kills it.
✈ Fly it around the world
What is Fruit Fly Airlines?
It has two parts. Meet the fly is a one-minute zoom from the whole fly down to a single molecule of acetylcholine, then free exploring: click any of its neurons to see what it is, fire it, silence it, or follow a smell or an escape through its wiring. Fruit Fly Airlines is the game: flap between each city's landmark and its clouds, one continent per level, and share the boarding pass when your fly dies.
Is the fly's brain real?
The wiring is real. Every neuron, where it sits and what it connects to comes from MaleCNS v1.0, a map of a real male fruit fly's brain and nerve cord traced from electron-microscope images by FlyEM (HHMI Janelia), the University of Cambridge, MRC LMB and Google Research, shared under CC BY 4.0. How activity flows through that wiring is a simple model we wrote: the map records who connects to whom, not the fly's thoughts. The body is a micro-CT scan from NeuroMechFly (EPFL), walking with joint angles recorded from real flies.
How many neurons does a fruit fly have?
This fly has 165,122 neurons in its brain and nerve cord, all of them drawn where they really are. About two in three are predicted to use acetylcholine, the fly brain's main "go" signal (in your brain, glutamate does that job). You have about 86 billion.
What is a connectome?
A complete wiring diagram of a nervous system: every neuron and every connection between them. The fruit fly is the most complex animal with a complete one. The game uses its 2,749,394 strongest connections, made of 67,172,937 synapses.
How does the fly's own brain fly the game?
The game is rendered from the fly's head into its 1,769 eye columns. Their signals run through the real wiring to its looming detectors, the neurons that notice something rushing towards it (LC4, LPLC2, LPLC1, LC16). When danger below outweighs danger above, it flaps. It's a reflex, honest rather than good: it averages about three cities.
Can you fly all the way around the world?
Yes, but only the best players will. Clear all eleven continents, every one of the 166 cities once, and your fly has flown around the world: it becomes a Circumnavigator, with a gold boarding pass and a place in the Hall of Fame. Each continent is faster, narrower, gustier and more unsteady than the last, but every gap stays within a fly's physical reach: hard, never impossible.
Where do the weather and local times come from?
Every city shows its real local time and, from Open-Meteo, its weather right now: rain makes the fly heavier, wind buffets it, and a real storm in tornado country brings a tornado. When the fly dies, the city sends a postcard: something true about it, and what's special there today.
How are scores kept fair?
The server hands out each flight's route and weather, signed, and when the flight ends it re-flies it from your taps with the same physics the game uses. Only the result it works out itself can go on the world leaderboard or into the Hall of Fame.
Quick answers
- Is it free?
- Yes. It runs in a web browser, with no download and no account.
- Does it work on phones?
- The game is for computers for now. On phones you can watch the zoom into the fly and sign up to hear when the phone version arrives.
- Who made it?
- KekwanuLabs. Questions: hello@fruitflyairlines.com.
- What about my data?
- Very little is kept, and there are no cookies. See privacy.
Connectome: MaleCNS v1.0, FlyEM / HHMI Janelia, University of Cambridge, MRC LMB and Google Research, CC BY 4.0. Body: NeuroMechFly v2, NeLy lab, EPFL, Apache-2.0. Weather: Open-Meteo.