Daily Bread for 11.3.22: Crows (Yes, Crows)

Good morning.

Thursday in Whitewater will be sunny with a high of 71. Sunrise is 7:32 AM and sunset 5:44 PM for 10h 11m 24s of daytime. The moon is a waxing gibbous with 73.8% of its visible disk illuminated.

Whitewater’s Landmarks Commission meets at 6 PM

On this day in 1812, Napoleon’s armies are defeated at the Battle of Vyazma.

These are turbulent times, often unnecessarily and destructively so. In former times like these, people with far more important roles than writing yet took time for occasional diversions.

In that spirit, something interesting about crows — Diane Kwon reports Crows Perform Yet Another Skill Once Thought Distinctively Human

Crows are some of the smartest creatures in the animal kingdom. They are capable of making rule-guided decisions and of creating and using tools. They also appear to show an innate sense of what numbers are. Researchers now report that these clever birds are able to understand recursion—the process of embedding structures in other, similar structures—which was long thought to be a uniquely human ability.

Recursion is a key feature of language. It enables us to build elaborate sentences from simple ones. Take the sentence “The mouse the cat chased ran.” Here the clause “the cat chased” is enclosed within the clause “the mouse ran.” For decades, psychologists thought that recursion was a trait of humans alone. Some considered it the key feature that set human language apart from other forms of communication between animals. But questions about that assumption persisted. “There’s always been interest in whether or not nonhuman animals can also grasp recursive sequences,” says Diana Liao, a postdoctoral researcher at the lab of Andreas Nieder, a professor of animal physiology at the University of Tübingen in Germany.


This paper prompted Liao and her colleagues to investigate whether crows, with their renowned cognitive skills, might possess the capacity for recursion as well. Adapting the protocol used in the 2020 paper, the team trained two crows to peck pairs of brackets in a center-embedded recursive sequence. The researchers then tested the birds’ ability to spontaneously generate such recursive sequences on a new set of symbols. The crows also performed on par with children. The birds produced the recursive sequences in around 40 percent of trials—but without the extra training that the monkeys required. The results were published today in Science Advances.

The discovery that crows can grasp center-embedded structures and that they are better at doing so than monkeys “is fascinating,” says Giorgio Vallortigara, a professor of neuroscience at the University of Trento in Italy, who was not involved in the work. These findings raise the question of what non-human animals might use this ability for, he adds. “They do not seem to possess anything similar to human language, thus recursion is possibly relevant to other cognitive functions,” he says. One speculation is that animals might use recursion to represent relationships within their social groups.

(Hat tip to Joe Ragazzo’s newsletter for the link to the story.) 

There are some doubts, as Kwon’s story reveals, about how much crows truly understand, but the findings will likely take time to sort out through other tests.

 Adorable Beaver Goes Viral for Feuding With Her Rival:

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