You would think that Thanksgiving is already over when visiting most stores as there are Christmas decorations and merchandise everywhere. Reds and greens are popular colors for Christmas decorations and dog toys. However, a new study suggests that your dog may be red-green color blind.
The study examined the ability of dogs to detect colors by exposing animals to a colored image on a screen and measuring the eye, head and whole-body movements in response. The colored image showed a red cat in various running positions surrounded by a green background (shown above). Alternatively, dogs were shown achromatic versions of the running cat images. No motivational or reinforcements were provided to avoid simply assessing learned behaviors.
This doggie-vision test is much like the red-green color vision test for humans. In the human version of the test, normal vision allows people to see the number 26 on the Ishihara plate no. 22 (shown above). Humans with red-green color blindness, on the other hand, only see the number 2 as the number 6 is actually a slightly different shade.
The researchers found that dogs paid the most attention to the feline silhouettes (B-Cat) followed by the red-green moving animations of the running cats using the red color from the Ishihara plate no. 22 (RG-Cat-2). However, when shown the cat images using the shade of red like the number 6 in the image (i.e. RG-Cat-6), the response was much less. Although the number of animals examined was rather small (only 16), these findings provide evidence that your dog may be red-green color blind.
M Siniscalchi, S d’Ingeo, S Fornelli, A Quaranta. Are dogs red-green colour blind? Royal Society Open Science. Published 8 November 2017.DOI: 10.1098/rsos.170869
Categories: Comparative Physiology