The theory of the "wisdom of the crowd" has been used to explain everything from the overall accuracy of Wikipedia to the logic of democracy. And in general, that principle is true: Choices made by many are usually better than those made by a few or one.
But new research from Arizona State University and Uppsala University in Sweden adds a caveat to that notion, showing that while crowds might indeed be wise when it comes to making tough, close calls, they are actually worse than individuals at choosing between two options, one of which is vastly superior to the other. When the choice is easy, in other words, the crowd can actually be pretty dumb.
For this study, the researchers used ants, given their propensity for acting as a group. The bugs were tasked with something humans might relate well to: Apartment hunting. Specifically, they were supposed to move from their existing dwelling to a new "house" -- one of two hollowed-out chunks of balsa wood, one of which was darker than the other. And if you're an ant, darker is better.
When they were hunting as a group, the ants made their choice by checking out the two houses, reaching a quorum on one or the other, and recruiting other ants from the home nest to come over. When the difference between the two houses was very slight, it helped to have a big group scouting together: Both places were pretty nice, it seemed, so more ant-votes made it more likely that the "right" house would be chosen. Eventually, enough ants would pick the nicer house, and they would recruit the rest of the colony to move in.