A Digital Fly Brain Has Taken Over the Internet

A full digital map of a male fruit fly brain has become an internet toy. Since it was released earlier this month, people have dropped it into Minecraft, Doom, Beat Saber, and other virtual setups, and the results have spilled across social feeds in a hurry.

The model is called a connectome, and this one maps more than 166,000 neurons in the nervous system of an adult male Drosophila fruit fly. HHMI Janelia Research Campus built it with Google Research, and the team says MaleCNS v1.0 is the first finished connectome of an entire male Drosophila central nervous system. It follows the first adult female fruit fly connectome, released in 2024.

That part matters because fruit flies are a workhorse for science. They reproduce quickly, adapt easily, and are cheap to study, which makes them useful model organisms. Researchers want these digital brains to help with neuroscience, pharmacology, biotechnology, artificial intelligence, and more. But the internet saw a different opportunity first.

Evan Sinclair Smith, a computer science graduate student at Georgia Tech, kicked off the viral wave by programming the fly brain to run inside Minecraft. He said the response has been wild, and other people quickly built on it. The fly has since been used to trade bitcoin, write LinkedIn posts, retire to a virtual fruit fly heaven, and even become “bi fly” in a project by entrepreneur and AI researcher Nico Christie.

There’s also been some hand-wringing online about what all this means, but the source is clear on one point: MaleCNS v1.0 is only a digital map. It has the wiring and structure, not the biochemical machinery of a real fly, and it is not conscious in any biological sense. Still, the bigger scientific prize is obvious. With male and female fly connectomes now available, researchers can compare how the two sexes are wired — and dream a lot bigger, even if the human brain, at 86 billion neurons, is a very different beast.