[Animals] Crows outthink monkeys, can grasp recursive patterns

[BirSaNN]

In cognitive tests for recognizing certain types of patterns, crows outperformed monkeys.

Crows are notoriously clever — the songbirds can use tools, understand the concept of zero and follow basic analogies. Now, a new study suggests that their grasp of one complex cognitive principle in particular is better than that of monkeys and comparable to that of small children.

Researchers found that crows can distinguish paired elements buried in larger sequences, a cognitive ability known as recursion. Consider the sentence: "The cat the dog chased meowed." Although the sentence is admittedly a grammatical nightmare, most adults would quickly understand that the cat meowed and that the dog chased the cat. This capacity to pair elements like "cat" to "meow" and "dog" to "chase" in a sentence, or any sequence, was once thought to be a uniquely human trait. 

The new study, however, suggests that crows can do it too. And this latest research builds on previous work demonstrating the existence of recursive reasoning among monkeys. "One of the most distinguishing features of human communicative cognition may turn out not to be that human-specific after all," lead author Diana A. Liao, a postdoctoral candidate at the University of Tübingen in Germany, told Live Science in an email.

 

Grammar isn't the only place where recursion occurs. Our ears can distinguish a musical phrase within a larger piece, and our minds can set aside a mathematical expression embedded between parentheses. Indeed, a 2020 study published in the journal Science Advances(opens in new tab) demonstrated that people can follow recursive patterns even without a formal background in reading and mathematics. In that study, people from isolated Amazonian tribes identified recursive patterns about as well as adults living in the U.S. did. Nonhuman primates also demonstrated an ability to understand recursion; the same study found that rhesus monkeys (Macaca mulatta) were only slightly inferior to toddlers when it came to distinguishing paired elements, such as opened and closed brackets, from a morass of symbols.

 

link: https://www.livescience.com/crows-understand-recursive-reasoning