GLOSSARY
Words after sunset.
Dim light
Some illumination is present, even when a place seems dark to a person.
Lightless
No light is available to be reflected. A reflective eye layer cannot create illumination.
Retina
Light-sensitive tissue at the back of the eye.
Rod
A type of light-sensitive retinal cell important for dim-light vision.
Cone
A type of light-sensitive retinal cell involved in color vision.
Tapetum
A reflective layer that can return incoming light through the retina.
Eyeshine
A visible reflection from light entering the eye, not a vision score.
Unknown
A detail not established. Do not turn it into an answer by testing a dog.
Yamaue et al.: Rod density and the canine tapetum ↗Source for the factual context, not independent review of this page.
Zoetis: Can dogs see in the dark? ↗Source for the factual context, not independent review of this page.