What can a fruit fly do? Buzz around ripe bananas, sure. But maybe, a whole lot more. Like parallel park. Or play Minecraft.
Creative internet users have in recent days taken a complete map of a fruit fly’s 166,000 neurons, published by Google, and made simulated flies do some things that are pretty impressive, given that these insects have a brain the size of a poppy seed. One has been trained to solve a Rubik’s Cube. Another dances to the Village People’s “Y.M.C.A.” in response to four tones. Others have envisioned fruit flies playing poker and blackjack and slicing a doner kebab.
In general, the goal of these engineers and artists is not to show what a fly can do, but “what’s the dumbest thing we can make it do,” said Mark Unthank, a software developer who got a fly to parallel park a car after hundreds of failed attempts. Mr. Unthank, who lives in Italy, also programmed a fly to use a car’s blinkers when turning because he was frustrated that so few human drivers seem to use them.
“That’s how easy it is,” he said. “Even a fly could do it.”
Producing the map of the fly’s brain, on the other hand, was anything but easy. It was serious research meant to advance the study of neuroscience.
For years, researchers worked to develop sophisticated imaging techniques to map the connections within the nervous systems of various organisms. Some have focused on fruit flies because of the insect’s relative lack of complexity; while the fly has just 166,000 neurons, a human being has about 86 billion.
Scientists call the neural maps connectomes, similar to the genomes that help map the genes that determine an organism’s traits.
Researchers at the Janelia Research Campus at the Howard Hughes Medical Institute in Virginia completed the new map of the adult male fruit fly’s brain in partnership with Google. The effort involved hundreds of scholars.
Scientists hope the map will help them understand how animals perceive the world, store memories and react to stimuli.
“Our goal is not simply to demonstrate that a fly brain is capable of generating movement in a fly — which we obviously know — but how,” said Nelson Spruston, a neuroscientist who is vice president and executive director at the Janelia campus.
The institute is now working to develop maps of the brain in two fish — a larval zebrafish and an adult Danionella. The research, it said, could one day reveal how humans develop Alzheimer’s or depression.
For now, the Janelia researchers have been pleasantly surprised to see fruit flies driving cars and playing video games.
“I certainly did not imagine this kind of application of our work, but I think it’s exciting and it’s fun, and it sort of demonstrates the power of open science,” Dr. Spruston said.
Arie Matsliah, a research scientist at Princeton University, said the release of the maps has coincided with a spike in the capability of A.I.-powered coding tools that allow people to create simulations with just a few simple prompts. Dr. Matsliah helped develop FlyWire Codex, an online portal for the maps that has seen thousands of downloads a day, he said.
“It’s almost becoming a meme now,” he said. “Everyone is trying different things.”
Alex Wormuth, a software engineer in Tulsa, Okla., said he used an OpenAI tool to make the fly play the 1990s first-person shooter video game Doom, which he named Doomfly. If the fly shoots and kills an enemy, it triggers the insect’s dopamine receptor, encouraging it to kill again to survive, he said.
So far, the fly is not very good at Doom, he concedes.
“It has been able to kill an enemy,” he said, “but I don’t think it’s learned that’s what it needs to do to beat the game.”
Mr. Wormuth has also given a simulated fruit fly $100 in real bitcoin, with the option to buy, sell or hold. For a brief period on Friday, he said, the fly made about $1 before the cryptocurrency’s price dropped.
The simulations, although based on a fruit fly brain, do not actually account for the complex interactions between neurons, muscles and other systems in a real fruit fly, Dr. Matsliah said.
“They assume things, or they substitute the missing components with things that are not biological,” he said.
That includes modifying the strength of the connections between neurons, which makes the simulations “substantially different from a real fly,” Dr. Spruston said.
“It’s not like a fly brain in real life can play Doom, obviously,” he added.
“Nevertheless, there is some reality there,” Dr. Matsliah said.
Parallel to the existential anxieties brought up by recent rapid advancements in artificial intelligence, some people have wondered whether the flies might have some form of consciousness as they twist and turn the faces of a Rubik’s Cube or try to win at poker.
Mr. Wormuth, the Doomfly creator, has his doubts.
“I don’t believe that’s happening,” he said. “But I think it’s an interesting thought experiment because, someday, we may have something like this for the human brain.”
