Baby chickens have left-right number bias 'like humans'
Scientists in Italy say they have found that baby chickens associate low and high numbers with left and right, respectively - just like humans.
This suggests that a "mental number line" might be an ancient evolutionary development, rather than something we acquire through education.
In experiments published in Science magazine, 60 chicks were shown patterns of shapes representing different numbers.
If it was lower than the previous number they had seen, chicks associated a new number with the left - or the right, if it was higher.
Humans are known to have left-right bias when thinking about quantities but this innate left-right association has not been seen in animals before.
Video courtesy of Dr Rosa Rugani, University of Padova
29 Jan 2015