The olfactory capability of dogs to discriminate between different quantities of food


A previous study failed to find evidence that dogs could use olfactory cues to discriminate between 1 and 5 hot dog slices presented on a single trial (Horowitz et al., Learning and Motivation, 44, 207–217, 2013). In the experiments reported here, multiple trials were used to test dogs’ ability to use olfaction to choose one of two opaque containers under which a larger number of food items was placed. In Experiment 1, dogs chose between 1 and 5 hot dog slices. In Experiments 2 and 3, we examined dogs’ ability to discriminate between numbers of hot dog slices that varied in the numerical distance and the ratio between the smaller and larger quantities. Experiment 4 explored olfactory discrimination between quantities of a different food, dog kibble. Experiments 13 all showed that dogs used olfactory stimuli to choose the larger number of hot dog slices, but Experiments 2 and 3 revealed no effects of distance or ratio between numerical quantities. In Experiment 4, dogs failed to discriminate between 1 and 5 pieces of dog kibble. Factors that allow dogs to use olfactory cues to discriminate between quantities are discussed.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2
Fig. 3


  1. Beran, M. J. (2001). Summation and numerousness judgments of sequentially presented sets of items by chimpanzees (Pan troglodytes). Journal of Comparative Psychology, 115, 181–191.

    Article  PubMed  Google Scholar 

  2. Brannon, E. M., & Merritt, D. J. (2011). Evolutionary foundations of the approximate number system. In S. Dehaene & E. Brannon (Eds.), Space, time and number in the brain: Searching for the foundations of mathematical thought (pp. 207–224). Elsevier.

  3. Cablk, M. E., Sagebiel, J. C., Heaton, J. S., & Valentin, C. (2008). Olfaction-based detection distance: A quantitative analysis of how far away dogs recognize tortoise odor and follow it to source. Sensors, 8, 2208–2222.

    Article  PubMed  Google Scholar 

  4. Dehaene, S. (2001). Subtracting pigeons: Logarithmic or linear? Psychological Science, 12, 244–246.

    Article  PubMed  Google Scholar 

  5. Dehaene, S., Dehaene-Lambertz, G., & Cohen, L. (1998). Abstract representations of numbers in the animal and human brain. Trends in Neurosciences, 21, 355–361.

  6. Horowitz, A., Hecht, J., & Dedrick, A. (2013). Smelling more or less: Investigating the olfactory experience of the domestic dog. Learning and Motivation, 44, 207–217.

    Article  Google Scholar 

  7. Kalmus, H. (1955). The discrimination by the nose of the dog of individual human odours and in particular of the odours of twins. The British Journal of Animal Behaviour, 3, 25–31.

    Article  Google Scholar 

  8. King, J. E., Becker, R. F., & Markee, J. E. (1964). Studies on olfactory discrimination in dogs: (3) Ability to detect human odour trace. Animal Behaviour, 12, 311–315.

    Article  Google Scholar 

  9. Krichbaum, S., Rogers, B., Cox, E., Waggoner, L. P., & Katz, J. S. (2020). Odor span task in dogs (Canis familiaris). Animal Cognition, 23, 571–580.

    Article  PubMed  Google Scholar 

  10. Lo, K. H., Macpherson, K., MacDonald, H., & Roberts, W. A. (2019). A comparative study of memory for olfactory discriminations: Dogs (Canis familiaris), rats (Rattus norvegicus), and humans (Homo sapiens). Journal of Comparative Psychology, 134, 170–179.

    Article  PubMed  Google Scholar 

  11. Lo, K. H., & Roberts, W. A. (2019). Dogs (Canis familiaris) use odor cues to show episodic-like memory for what, where, and when. Journal of Comparative Psychology, 133, 428–441.

    Article  PubMed  Google Scholar 

  12. Macpherson, K., & Roberts, W. A. (2013). Can dogs count? Learning and Motivation, 44, 241–251.

    Article  Google Scholar 

  13. Nieder, A. (2019). A brain for numbers: The biology of the number instinct. MIT Press.

  14. Petrazzini, M. E. M., Mantese, F., & Prato-Previde, E. (2020). Food quantity discrimination in puppies (Canis lupus familiaris). Animal Cognition, 23, 703–710.

    Article  Google Scholar 

  15. Petrazzini, M. E. M., & Wynne, C. D. L. (2016). What counts for dogs (Canis lupus familiaris) in a quantity discrimination task? Behavioural Processes, 122, 90–97.

    Article  Google Scholar 

  16. Piazza, M. (2010). Neurocognitive start-up tools for symbolic number representations. Trends in Cognitive Sciences, 14, 542–551.

    Article  Google Scholar 

  17. Plotnik, J. M., Brubaker, D. L., Dale, R., Tiller, L. N., Mumby, H. S., & Clayton, N. S. (2019). Elephants have a nose for quantity. Proceedings of the National Academy of Sciences of the United States of America, 116, 12566–12571.

    Article  PubMed  PubMed Central  Google Scholar 

  18. Polgár, Z., Kinnunen, M., Újváry, D., Miklósi, Á., & Gácsi, M. (2016). A test of canine olfactory capacity: Comparing various dog breeds and wolves in a natural detection task. PLOS ONE, 11, Article e0154087.

    Article  PubMed  Google Scholar 

  19. Quignon, P., Giraud, M., Rimbault, M., Lavigne, P., Tacher, S., Morin, E., Retout, E., Valin, A., Lindblad-Toh, K., Nicolas, J., & Galibert, F. (2005). The dog and rat olfactory receptor repertoires. Genome Biology, 6, R83.

    Article  PubMed  PubMed Central  Google Scholar 

  20. Roberts, W. A. (2005). How do pigeons represent numbers?: Studies of number scale bisection. Behavioural Processes, 69(1), 33–43.

    Article  PubMed  Google Scholar 

  21. Roberts, W. A. (2010). Distance and magnitude effects in sequential number discrimination by pigeons. Journal of Experimental Psychology: Animal Behavior Processes, 36, 206–216.

    Article  PubMed  Google Scholar 

  22. Rouquier, S., Taviaux, S., Trask, B. J., Brand-Arpon, V., van den Engh, G., Demaille, J., & Giorgi, D. (1998). Distribution of olfactory receptor genes in the human genome. Nature Genetics, 18, 243–250.

    Article  PubMed  Google Scholar 

  23. Rowe, C. (1999). Receiver psychology and the evolution of multicomponent signals. Animal Behaviour, 58, 921–931.

  24. Ward, C., & Smuts, B. B. (2007). Quantity-based judgments in the domestic dog (Canis lupus familiaris). Animal Cognition, 10, 71–80.

    Article  PubMed  Google Scholar 

  25. Wye, M. V. (2010). U.S. Publication Number: US 2010/0095896 A1. U.S. Patent and Trademark Office.

  26. Zozulya, S., Echeverri, F., & Nguyen, T. (2001). The human olfactory receptor repertoire. Genome Biology, 2, Article research0018.1.

    Article  Google Scholar 

Download references


Support for this research was provided by a Discovery Grant from the Canadian Natural Sciences and Engineering Research Council to W. A. Roberts.

Author information



Corresponding author

Correspondence to William A. Roberts.

Additional information

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Jackson, S.M., Martin, G.K. & Roberts, W.A. The olfactory capability of dogs to discriminate between different quantities of food. Learn Behav (2021).

Download citation


  • Olfaction
  • Dog
  • Quantity discrimination
  • Distance effect
  • Ratio effect
  • Food type