Mathematics is often called a universal language, understood by all intelligences in our universe—and perhaps beyond. We know crows are incredibly smart birds. The term “crow” actually refers to all 35 species in the Corvus family. Their intelligence continues to amaze us with new discoveries. Recently, carrion crows were found to count up to four vocally, showcasing their impressive mental and vocal abilities.
Feathered Mathematicians
In a recently published paper in the Science journal, a University of Tubingen (Germany) research team in Animal Physiology comprised of Diana A. Liao, Katharina F. Brecht, Lina Veit (Neurobiology of Vocal Communication), and Andreas Nieder have gained new ground in finding that carrion crows were able to vocally count out their mathematical deductions by tallying a count. The team was aware that crows possessed numerical comprehension but wanted to determine if they could do so out loud, much as a young learning child would. The team discovered that the crows in the tests used specific vocalizations, different for each number up to four.
This amazing feat is not an easy one. According to the study abstract (here), even toddlers have difficulty in voicing numbers. Three crows were used in the tests. They were trained to caw in numerical process as certain sounds in value were played back. The sounds were four caws, three drumbeats, two register dings, and a single guitar chord. The crows would then caw (or count) out the number of the sounds heard. Other tests were performed using a visual screen with Arabic numerals in the hope that the birds would recognize and “vocalize” the number by a corresponding number of caws.
Counting Crows
With the visual cues, crows were encouraged to tap the screen to indicate they were finished with the count. If successful, the crow was rewarded with a mealworm. With the count, the birds displayed a variance of success the more they were expected to count to. At one, they recognized the number and were 100% accurate in vocalizing the number. Number two resulted in 60% accuracy, number three in 50%accuracy, and number four (the toughest number) at 40% accuracy. The birds were reportedly not appreciative of being asked to count to that level and were often attempting to finalize the unfinished count. Regardless of accuracy rates, the reality that the crows were counting at all is an amazing discovery.
Another intriguing find was that the birds paused before cawing their answer, suggesting they were actively thinking and forming coherent thoughts before responding.
What next will we discover about our feathered friends?