Do chicks, like humans, have a left-right mental "number line," with spatial correlates to number values? Recent research demonstrates that, indeed, baby chickens associate low numbers with left and high numbers with right, just like we do. The chicks were presented with a number, then two of a different number side by side (behind which treats were sitting); they tended to retrieve the treats from the left if the new number was lower, and right if it was higher.
These incredible results echo many studies of humans, whereby (for example) babies prefer arrangements that increase in value from left to right, and adults respond more quickly to large numbers with their right hand (and small with left). Taken together, it would seem that the primitive evolutionary condition in tetrapod brains is some sort of internal wiring towards left-right ordering of quantities. Scientists have called this our mental "number line."
In short, this is astounding! Read the full article here: http://www.sciencemag.org/content/347/6221/534
Thank you to Paul Manning, Oxford Zoology DPhil candidate and Vine superstar, for sending along this article!
Scientists in Italy have found that baby chickens associate low and high numbers with left and right, respectively - just like humans. In a series of experiments, 60 newborn chicks were shown patterns of shapes representing different numbers, before choosing a direction. Humans are known to use a "mental number line" to think about quantities but this innate left-right association has not been seen in animals before.