Dogs value quantities the same as humans
We are born with a primitive sense of quantity, which allows us to estimate the approximate number of objects at a glance. This intuitive ability does not require a higher understanding of numbers and can be found across the animal kingdom, for example in monkeys, fish and even bees. However, until now it has been unclear whether the underlying neuronal mechanisms are also the same across different species.
Lauren Aulet and her team at Emory University in Atlanta have now shown that this could be the case, at least for mammals. The researchers used functional magnetic resonance imaging to scan the brains of 11 domestic dogs as they viewed sequential images of varying numbers of dots. The idea here: Brain areas that are responsible for the sense of numbers should be more active when the difference between consecutive amounts is very large - for example when ten points are followed by only two.
Indeed, in eight of eleven dogs, activation in the parietotemporal lobe was dependent on the amount of dots, regardless of the total area covered by the dots. This is a clear indication that dogs make spontaneous quantity calculations using the same brain region that previous studies have shown is also associated with the primitive number sense in humans and other primates. The researchers conclude that this is a neural mechanism that goes back at least 80 million years in mammalian evolution. Unlike animals, however, humans build higher mathematical abilities on top of this primitive number sense over the course of their development and also use their prefrontal cortex to do so.
