Color vision in the California sea lion (Zalophus californianus)

  title={Color vision in the California sea lion (Zalophus californianus)},
  author={Ulrike Griebel and Axel Schmid},
  journal={Vision Research},
Three California sea lions were trained to discriminate between a colored stimulus and two shades of gray in a 3-fold simultaneous choice situation. The colors blue, green and red were tested against shades of gray varying from low to high relative brightness. All animals distinguished blue from gray; two animals also distinguished green from gray; but none discriminated between red and gray. Our data suggest that California sea lions have dichromatic color vision. Their ability to discriminate… 
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