Crows make decisions twice as fast as humans, German study finds (Oct. 22)
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Researchers at the University of Tübingen in Germany found that carrion crows made a visual decision in 235 milliseconds on average, about twice as fast as humans and monkeys.
With clear signals, the crows chose correctly nearly 100 percent of the time, according to the university.
Brain signals tied to the choice showed up about 70 milliseconds after the crows saw the moving dots, long before they pecked an answer.
The study, by Philipp Schmidbauer and Professor Andreas Nieder, was published Oct. 22 in the journal Science.
Nature & Wildlife: This is the first story in a new Willamette News series celebrating the animals and wild places around us.
The next time a crow eyes you from a power line in Salem, consider this: it may be making up its mind faster than you can.
Researchers at the University of Tübingen in Germany report that carrion crows, a close European relative of the American crows we see across the Willamette Valley, make visual decisions about twice as fast as humans and monkeys. The study, "Ultrarapid decision-making in an avian brain," by Philipp Schmidbauer and Professor Andreas Nieder of the university's Institute of Neurobiology, was published Oct. 22 in the journal Science.
Dots, a touchscreen and a peck
In the experiment, two carrion crows watched a pattern of moving dots on a touchscreen and had to decide whether the dots were mostly moving left or right. They answered by pecking a target on the left or right side of the pattern, according to the university's announcement.
The crows took just 235 milliseconds on average to identify the direction and give their answer, while staying highly accurate.
"Even when the patterns of motion were hard to recognize, the crows' decisions were still better than random choices," Schmidbauer said in the announcement, "and with clear signals, they achieved an accuracy of nearly 100 percent."
Inside a crow's brain
The team recorded neurons in the nidopallium caudolaterale, a key region of the bird brain that the university compares to the prefrontal cortex in humans. As early as 70 milliseconds after the dots appeared, the neurons' signals for left and right began to split apart, long before the birds responded.
That activity built up gradually as each decision formed, until it reached a threshold and the crow made its choice. The neurons reflected both how strong the visual information was and which direction the bird picked.
"These findings show that neuronal dynamics in the avian brain are consistent with established models of decision-making in humans and non-human primates," Nieder said.
Birds don't have the layered cerebral cortex that people and monkeys do. Even so, their differently built brains appear to follow the same basic rules for making decisions, and to do it twice as fast. Nieder suggested the speed may come from what birds need to survive.
"Birds rely on their vision to carry out precise, rapid maneuvers during flight and to guide their beaks towards objects when foraging," he said. He added that more research is needed to pin down exactly what gives them the edge.
Why scientists call them feathered apes
Crows and their relatives are often nicknamed "feathered apes" because their problem-solving rivals that of primates. Nieder has leaned into the comparison himself: earlier this year he published a paper in the journal Lab Animal titled "Feathered primate of the air: the carrion crow as model in cognitive neuroscience."
Our crows in the Willamette Valley
You don't have to travel to Germany to watch these minds at work. The Oregon Department of Fish and Wildlife says the American crow is abundant in the south Willamette Valley, with sightings spread evenly through the year, and describes crows as birds of superior intelligence that can learn and make decisions.
Fall is a good time to start paying attention. In spring and summer, crows split into family groups to nest, and last year's young often help raise the new chicks. In fall and winter, crows forage by day and gather in the evening in large communal roosts, according to Bird Alliance of Oregon. The group describes the evening gathering before the birds settle in as a "raucous happy hour."
Up the road, Portland's downtown winter roost can top 20,000 crows at its peak from December through February, according to Bird Alliance of Oregon.
So the next time a crow snatches a dropped french fry in a Salem parking lot before you can react, give it some credit. Science says it was probably thinking twice as fast as you were.
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