Humans have a natural tendency to “line up” numbers. If given a set up numbers to work with people will generally place them on a “mental number line” even if they are not asked to do so. This phenomenon is so common that many researchers believe that it is hard wired into the brain and not part of culture or education.

Now, a team of Italian researchers suggests that this tendency may be even more hard wired than we thought. The researchers, led by Rosa Rugani, a psychologist who at the time was at the University of Padova demonstrated a preference for “numbers” on the right of the line.

The chicks were taught that mealworms were available behind white plastic tiles which were placed with equal numbers of red tiles which offered no reward. According to research, published in the journal science, the chicks showed a preference for the left when presented with a small number of squares and the right when the number of tiles was large.

In their study, the researchers said that the findings supported the idea of a natural left-right orientation for numbers buried at some primordial level of the brain.

This is supported by other recent studies that showed that people in Arabic speaking countries, where text is read right to left, the mental number scale is also reversed. According to the study this suggests “a universal cognitive system which is available shortly after birth.”

While the suggestion that our brains naturally associate numbers with space appears to hold up so far. The orientation of the number line, or number space, however may be cultural.

A 2008 study, also published in Science put the Mundurucu to the test. The Amazon aboriginal group has little or no formal education and showed a tendency to specially represent numbers. However, the Mundurucu used a logarithmic scale instead of a linear one.

When presented with panels marked with an equal number of squares the chicks chose to look behind the left hand side with much higher frequency. However when the number of squares on the panels was larger than five, the chicks tended to go to the right. Like humans, chicks seemed to adjust their choices based on the numbers they were presented with.

“We cannot think of any other, and simpler, explanation for the behavior of the chicks than assuming the training number is 1) remembered and 2) compared with the number seen at test,” Dr. Rugani said in an email to the New York Times.

This should not, however, be mistaken for an ability to count or do mathematics. A number of other animals including monkeys, pigeons and some fish have shown the ability to ‘count’ in other studies. To date this has been seen as an indication that they have an ability to distinguish numerical magnitude rather than a specific number.

A pigeon, for example, may be able to distinguish between a large pile of seeds in one pile and a few seeds in a second pile, or between a large group of predators and a small group. That does not mean that they know that the specific number of seeds in the ’large pile’.

What the latest research does do is provide further evidence that the perception of a relationship between numbers and space seems to exist in the brain and that perception appears to be very, very old.

“We have brains that evolved for fighting and finding food, not for doing calculus. So one of the hopes of this kind of research is that it will tell us something about the basic building blocks we have access to in building up these more human concepts,” Tyler Marghetis of the University of California San Diego told the Times.