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.

The work appears in Science magazine.

Dr Rossa Rugani, who led the experiments at the University of Padova, said it was impossible to know exactly what drove the chicks’ choices – but the results were clear.

“All we can judge is behavioural responses. Therefore, we don’t actually know if it is a real ‘number line’ but it strongly resembles what is observed in the human number line,” she told BBC News.

Humans show very consistent associations between spatial locations and numbers, but it is unclear how much of this develops automatically and how much we learn.

At seven months of age, babies prefer arrangements that increase from left to right. Adults show a bias whereby […]