Honeybee learning to categorise numbers as odd or even

This video shows researchers training a honeybee to choose even numbers. When the bee lands on a card presenting an even number of shapes she receives sugar water to drink. When the bee lands on a card presenting an odd number of shapes, she tastes a bitter liquid called quinine. In the video we see the bee inspect each card on the screen before making a correct choice on the card presenting an even number of 12 shapes.