There are certain abilities that separate humans from other animals. One such ability is the formation of a so-called mental number line, whereas smaller numbers are arranged to the left, and larger numbers are oriented to the right. However, not all researchers agree that this ability is uniquely human. In a recent study, researchers found that newborn chicks may be born with a predisposition to map numbers in a left-to-right manner.
In the study, published in Science, researchers used 3-day-old domestic chicks to gauge their innate ability to arrange numbers. In the experimental design, the team trained chicks to recognize a target quantity (either five or 20).