Science Past from the issue of January 26, 1963

DOGS FOUND COLOR-BLIND — Some animals are able to distinguish colors but others are practically color-blind, Dr. Gerti Duecker, zoologist of the University of Muenster, West Germany, has determined by a series of tests. Dr. Duecker found cats and dogs to be color-blind, although there is some evidence that some dogs have a faint sense of color. The color vision of mice, rats and rabbits is also not positive. The golden hamster and the opossum are definitely color-blind. Horses, deer, sheep, pigs, squirrels and martens can perceive colors, but only in certain parts of the spectrum. A few species are receptive only to reds and greens…. Most monkeys and apes resemble man in their capacity to see colors, and the chimpanzee is the most versatile of all.