The mirror test, in which animals are asked to demonstrate that they recognize their mirror image as “self” has become the gold standard to assess self awareness in animals. Few pass the test, including non-human primates, an elephant, dolphins, and a magpie. But how relevant is the test for species whose primary mode of identification may not be visual? Or species that lack the ability to demonstrate that they have recognized themselves?
Behavioral scientists have gone to great lengths to identify an alternative to the mirror test. Marc Bekoff of the University of Colorado, Boulder, went so far as to play with yellow snow to demonstrate that his dog recognized his own urine.
A recently published study took that work a step further and revealed that dogs may identify themselves through scent. The controlled experiment, published in Behavioural Processes (Horowitz, A., Smelling themselves: Dogs investigate their own odors longer when modified in an “olfactory mirror” test, Behav Processes 2017;143:17-24).
In this study, dogs spent less time examining their own urine in contrast to either their own urine modified with a foreign odor, or the foreign odor alone. The dogs spent longer with the modified urine than with the foreign odor, indicating that novelty alone does not explain the behavior. The author concludes that this study, like others of its kind, demonstrates a partial self-recognition.
What about cats? In spite of claims that some cats have passed the mirror test, because cats do react to images in mirrors, no cat has definitively passed this test. Research on self-awareness in cats lags behind the work being done in dogs.
For those who live with cats or dogs, the idea that they do not have even a limited sense of self-awareness is unthinkable. Our experiences with our animals suggest that the problem does not lie with animal awareness, but with our ability to evaluate it in a controlled study.
What do you think? Let us know!