Crows Make Visual Calls in 0.5 Seconds, Twice the Speed of Monkeys

Two carrion crows completed a standard primate decision test in about 0.5 seconds, roughly half the time monkeys need, according to a University of Tübingen study published on October 23, 2026. Neurobiologist Andreas Nieder and colleague Philipp Schmidbauer recorded brain activity from the birds as they worked through the task.

The experiment, known as the random-dot-motion task, presents a field of flickering specks on a screen. Some share of the dots drift in one direction, and the subject must judge whether motion exists and where it points. In primates, neurons in the neocortex accumulate that visual evidence until firing rates cross a threshold and the animal commits to an answer. Birds lack a neocortex, which left open how their brains handle the same computation.

Nieder and Schmidbauer placed two hand-raised carrion crows before a touch-sensitive monitor showing white dots on black. A portion of the dots drifted left, right, up, or down. The crows signaled a direction by pecking a target flanking the display, and a correct answer earned a mealworm. The setup mirrored the primate version in every respect except the response method: monkeys indicate choices with an eye movement.

Difficulty varied by how many dots moved together. At the easiest level, 81 percent moved coherently. At the hardest, 3 percent did, a signal barely distinguishable from noise. The team also ran a zero percent condition with no correct answer available. Nieder said the team deliberately kept the task identical to the monkey version: "We intentionally wanted to have exactly the same random-dot motion task."

The crows solved the task using the same mathematical logic as primates, and they reached decisions in about 0.5 seconds. Monkeys require roughly twice that time on the same task. The result indicates a brain without a neocortex can arrive at decisions through a comparable process. Nieder framed the central question behind the work: "How [would] a differently organized avian brain encode decisions?" The study was authored by Nieder and Schmidbauer at the University of Tübingen.

The crows performed at the same accuracy levels as primates across the range of difficulty, including the 3 percent coherence condition where dots barely differ from random noise. Researchers recorded neural activity from the birds throughout each trial, tracking how evidence accumulated before a peck was made.