When rats go shopping: Three is the magic number

Our lives would be unimaginable without knowledge of numbers. We buy 3 liters of milk, we eat 2 eggs for breakfast, and we cycle 65 km on Saturdays. Recent research shows that rats also have an abstract concept of number that they can put to use when seeking a reward.

Source: Psychonomic Society News - February 4, 2016 Category: Neuroscience Source Type: news