Volume 122, January 2016, Pages 90–97
Highlights
- •
- Dogs were presented with a spontaneous choice between two food quantities.
- •
- Dogs chose the larger amount of food irrespective of the number of items.
- •
- Accuracy was affected by the ratio between the two quantities.
- •
- These results suggest that in food choice task amount counts more than number.
Abstract
Numerous
studies have reported that animals reliably discriminate quantities of
more or less food. However, little attention has been given to the
relative salience of numerosity compared to the total amount of food
when animals are making their choices. Here we investigated this issue
in dogs. Dogs were given choices between two quantities of food items in
three different conditions. In the Congruent condition, the total
amount of food co-varied with the number of food items; in the
Incongruent condition the total amount was pitted against the
numerosity; and in the Controlled condition the total amount between the
sets was equal. Results show that dogs based their choice on the total
amount of edible food rather than on the number of food items,
suggesting that, in food choice tasks, amount counts more than number.
The presence of the largest individual item in a set did not bias dogs’
choices. A control test excluded the possibility that dogs based their
choices on olfactory cues alone.
Keywords
- Numerical competence;
- Quantity discrimination;
- Dog;
- Cognition
Copyright © 2015 Elsevier B.V. All rights reserved.
