Paul van Son

A single ant has 250,000 neurons. Your brain has 86 billion. That’s a 344,000x gap. And yet what you’re watching is a colony solving a category of problem that no computer can crack perfectly at scale. It’s called the Steiner tree problem. Given a set of points, find the shortest possible network connecting all of them. First posed in 1811, proved essentially impossible to solve perfectly in 1972 (the computing time grows so fast with size that the world’s fastest supercomputer stalls on a few hundred points). Still one of the hardest open problems in mathematics. Ants solve it with chemistry. When an ant walks a path, it leaves a chemical trail called a pheromone. That trail evaporates over time. Shorter paths get walked faster, so pheromone builds up before it fades. Other ants prefer stronger trails. The colony converges on the shortest route without any single ant knowing the full picture. Jean-Louis Deneubourg at the Free University of Brussels proved this in the early 1990s with a dead simple experiment: two bridges between a nest and food, one twice as long as the other. Within minutes, the colony picked the short one. In 1991, computer scientist Marco Dorigo took that discovery and turned it into an algorithm (a set of step-by-step instructions for a computer) called Ant Colony Optimization. It’s now used to route wires inside microchips with billions of transistors (one study found an 8% reduction in wire length over traditional methods), plan delivery truck routes, and manage internet traffic. The phone you’re reading this on was partially designed using math that ants figured out 100 million years before humans existed. A 2023 study out of Stanford and several other institutions found that turtle ants in the tropical forest canopy build trail networks across tangled branches and vines that approximately solve the Steiner tree problem with zero central control. No ant has any information about the full network. Each one just follows a rule: at each junction, go where the pheromone is strongest. The collective intelligence comes from thousands of these tiny decisions stacking up. Stanford biologist Deborah Gordon has studied this for decades. She compares it directly to how brains work: no single neuron tells the others what to do, but together they produce thought. A 2024 Rockefeller University study found that individual ants decide whether to leave the nest using the same yes-or-no process that brain cells use to decide whether to switch on. The colony is, in a real mechanical sense, a brain spread across thousands of bodies. In early 2025, a Weizmann Institute study pitted ant groups against human groups on a task almost identical to this video: navigating a T-shaped object through a series of obstacles. The bigger the human group, the worse they performed. Too many competing ideas about which direction to push. The bigger the ant group, the better they got. No ego, no debate, just pheromones and simple rules scaling into something that looks a lot like intelligence. 250,000 neurons each. No leader. No blueprint. Solving problems that stumped mathematicians for two centuries.

Wind turbines look so much better than a fossil fueled electricity generating plant. And they are what the future looks like (along with solar and battery storage)