Researchers have found that evolutionarily the ability to rough count independently developed in various living beings and is vital for them.
A review article systematizing work on understanding counts and numbers by various animals was published by German scientists in the journal Trends in Ecology and Evolution. We are talking about such different animals as bees, frogs and wolves, also including birds traditionally considered in this regard. The data show that although most of them are not able to count accurately, a rough count is characteristic of them in their natural habitat and is included in various life strategies, for example, when hunting, searching for food or protecting.
“Interestingly, we now know that numerical competence is present on almost every branch of the tree of animal life”, explains Andreas Nieder, a neuroscientist at the University of Tübingen, working to understand how animals distinguish and represent numbers, and in what form this information gets into their brain. – Different groups of animals obviously developed this trait independently of other lines, and this convincingly indicates that it should have adaptive value. Therefore, the ability to distinguish numbers must have strong benefits in survival and sexual selection.
Examples of understanding even by animals very distant from us of numbers and their relationships are right before our eyes, although we rarely think about it. For example, honey bees can remember how many landmarks they fly to the place where they need the plants to find the way back to the hive. “The last common ancestor between the bees and us primates lived about 600 million years ago”, says Nieder. “But nonetheless, they developed numerical competence, which in many respects is comparable to the numerical competence of vertebrates”.
Also, numerical competence can be observed in animals that need to be able to distinguish a food source with a large quantity from a source with a smaller one, as well as those who hunt in groups. For example, wolves need a flock to successfully hunt for any animal, and it should not be too large for everyone to get food, and not so small as to miss the game. So it is: for hunting moose a “gang” of six to eight individuals will gather, and a more “heavy” detachment, in which there will be nine to thirteen of them, will be needed for a bison.
Herbivores, who need not to attack, but to defend themselves, also know how to count, varying the size of the herds. According to Nieder, they are able to assess the likelihood of someone becoming a victim and use the number of group members in their daily lives.
The article also discusses how numerical competence can play a role in attracting a partner. For example, male frogs sing, “advertising” themselves to attract females. Females select from them those who have the most complex and multicomponent trill, counting the number of these sounds. Some insects have similar skills.
Despite numerous examples of numerical competence in animals, this subject is not too actively studied on its own. “Many of these behavioral data in the wild are usually collected as by-products or random results from other research questions”, says Nieder. The author believes that for a more accurate understanding of the development of these abilities in animals and their variability, as well as adaptation to new conditions, more detailed and directed studies are needed.
He also says that it is important to better understand the laws of perception and the underlying cognitive and neural mechanisms that determine numerical competence. This will help to figure out how decisions are made, which are then translated into activities.
To this end, next year Nieder and his laboratory will go on to study how the brain and individual groups of neurons process numbers in animals. “I hope that I can encourage behavioral ecologists to specifically explore numerical competence in the wild and thereby open up new areas of research”, he concludes.