Even bees know zero is less than one.

Area of Science:

• Animal cognition
• Comparative psychology
• Evolutionary biology

Background:

• Understanding numerical cognition in non-human animals provides insights into the evolution of this fundamental cognitive ability.
• Previous research has identified nonsymbolic number concepts in various species, including primates and children.

Purpose of the Study:

• To investigate whether honey bees possess a nonsymbolic concept of zero.
• To determine if honey bees can generalize ordinal rules to include the quantity zero.

Main Methods:

• Honey bees were presented with sequences of visual stimuli representing quantities.
• Experiments were designed to assess the bees' responses to empty sets (zero quantity) in comparison to sets with varying numbers of items.
• Behavioral responses were analyzed to infer the bees' understanding of numerical order.

Main Results:

• Honey bees demonstrated spontaneous generalization of an ordinal rule to empty sets.
• Bees treated zero as less than other whole numbers, consistent with an ordinal understanding.
• The findings suggest a nonsymbolic representation of zero in honey bees.

Conclusions:

• Honey bees exhibit a nonsymbolic concept of zero, similar to that observed in human children and monkeys.
• This capacity suggests that the cognitive foundations for understanding zero may have significant evolutionary roots.
• The study contributes to our understanding of the evolution of numerical cognition and abstract reasoning in animals.