If a fish can pass the mark test, what are the implications for consciousness and self-awareness testing in animals?
PLoS Biology February 1, 2019 M. Kohda, Takashi Hotta, Tomohiro Takeyama et al.
The ability to perceive and recognise a reflected mirror image as self (mirror self-recognition, MSR) is considered a hallmark of cognition across species. Although MSR has been reported in mammals and birds, it is not known to occur in any other major taxon. Potentially limiting our ability to test for MSR in other taxa is that the established assay, the mark test, requires that animals...