There’s a reason why black crows are called feathered monkeys. They can plan and remember information, are capable of complex learning, and can even use tools. Recently, scientists discovered another surprising skill in these smart birds.

It is known from past experiments that crows, like many other animals, recognize different numbers of objects in front of them. But counting out loud is a more difficult task and requires conscious control over the sounds produced, as well as understanding the numbers. New research published in the journal Scienceshowed that there were black crows (corvus crown) can “count” out loud by deliberately croaking a certain number of times in response to visual and auditory cues.

People become acquainted with arithmetic in their childhood years. Before children learn that the names and symbolic definitions of numbers correspond to a specific number, they learn to associate the number of spoken words with the number of objects. Therefore, when counting out loud, children often confuse the verbal definitions of numbers or change their order, but vocalize the required number. For example, after seeing three apples, a child may say one, one, one, two, four, five, not one, two, three.

Considering the advanced intellectual abilities of crows, a team of scientists from the Eberhard Institute for Neurobiology and the Karl University of Tübingen (Germany) decided to teach these birds a similar skill.

As the press release suggests, the experiment involved three black crows raised in a university laboratory. The researchers trained them to grunt one to four times when they saw corresponding Arabic numerals on a screen or in response to certain vocal stimuli. For example, a guitar chord meant humming once, and a drum was humming three times.

When the birds completed their task, they would indicate this by pressing a button on the screen with their beaks. The required number of crows were encouraged with treats such as mealworms. When the birds could not cope with the task, they were not treated, even if the number of croaks was close to the correct number.

Most of the time, the crows responded clearly to the stimuli, indicating that they understood the nature of the task, according to the scientists. However, sometimes mistakes occurred. Most often this occurred in cases where it was necessary to crawl three or four times.

Analysis of the experiment’s audio recordings showed that the birds paused to decide how many times to croak before emitting the sounds. So the crows planned the number of vocalizations. For example, they thought longer before a long sequence (three or four caws) than before a short sequence.

Commenting on the study, Professor John Marzlaff ( John Marzluff He called this the most important result of the new scientific study from the University of Washington (USA), which specializes in the study of crows. The longer reaction time means the birds need time to think about the task and transmit the signal from the brain to the muscles responsible for the sounds. Such a delay corresponds to imaginary planning. An expert who was not involved in the experiment explained that people behave the same way when asked a question that cannot be answered with certainty.

The results of the study confirm the idea that some birds, especially crows, can convey certain information to their relatives with the help of different numbers of sounds. For example, to warn of the presence of predators or the amount of food. According to scientists, this ability demonstrated by crows is reminiscent of the human ability to count and may be an “evolutionary precursor” to true counting.

Other researchers have previously found that understanding numbers increases animals’ chances of survival. In addition, American neuroscientists recently talked about the ability of the black-capped nuthatch to encode information about food stored in caches using “barcodes”.