抄録
Dolphins live in water and their vision plays an important role in their lives. However, there is only limited information available on the visual ability of dolphins. We examined achromatic color perception in a female bottlenose dolphin (Tursiops truncatus) using a conditional position discrimination procedure. The dolphin was first trained to choose one of the two pouched cardboards placed left or right corresponding to the sample painted either black or white. Then the subject was tested with achromatic color (gray) samples of varying brightness. The proportion of the dolphin's choice of the two locations gradually shifted according to the brightness of the sample, suggesting that the bottlenose dolphin has achromatic color perception similar to that of the human.
