Carrion crows outpace humans in lightning‑fast decisions

Scientists at the University of Tübingen and collaborators reported in the journal Science that carrion crows (Corvus corone) can make perceptual decisions about twice as fast as primates, including humans. In a controlled experiment, two captive crows named Iggy and Lemmy learned to interpret a screen of moving dots and peck to indicate the direction of the motion, earning a mealworm reward. Their average reaction time was 235 milliseconds, twice the speed of primates in similar tasks.

The task used a cloud of white dots that moved together in left‑or right‑ward motion while the rest of the dots moved randomly. The crows had to decide which way the coherent dots were moving and peck the corresponding side of the screen. Over thousands of trials, they answered correctly 74 percent of the time, matching the accuracy of primate studies while completing the task in half the time.

Neurophysiological recordings revealed that, 70 milliseconds after the dots appeared, activity in hundreds of neurons in the nidopallium caudolaterale – an area in the avian brain that is functionally comparable to the primate prefrontal cortex – predicted the birds’ choice. This rapid neural signature is consistent with the finding that the birds can decide in half the time of primates.

Crows lack the layered neocortex that mammals have, instead possessing a nuclear pallium. Despite this difference, the study shows that their brains can perform complex perceptual tasks with remarkable speed, highlighting the diverse evolutionary paths that lead to intelligence. The findings also underscore how comparative studies can reveal surprising capabilities in species whose lineages diverged from humans more than 300 million years ago.