It's true. Most animals with good night vision have blurry day vision.
One way you test it is by having one card with stripes and another card that is grey, each over a different button, and training the animal to press the button with the striped card to get a reward.
Then you just keep making the stripes narrower and narrower, until it can't tell the difference between the grey card and the stripes, and starts guessing.
One way you test it is by having one card with stripes and another card that is grey, each over a different button, and training the animal to press the button with the striped card to get a reward.
Then you just keep making the stripes narrower and narrower, until it can't tell the difference between the grey card and the stripes, and starts guessing.