Every AI system you have ever worked with learned its behavior from data. You define a loss function, run gradient descent, and the model adjusts its weights until it does what you want. That is how every LLM works. That is how every reinforcement learning agent works.

But a fruit fly never did any of that. Nobody trained it. No reward signal. No labeled examples. The behavior emerged from the wiring of its brain.

Researchers just demonstrated that if you copy that wiring into a computer, the exact same thing happens. The behavior emerges. Without training.

That is not just a neuroscience story. It is a direct challenge to one of the core assumptions of modern AI.