If I fits I sits: illusory contour susceptibility in domestic cats
I'm very sad I can't view the figures, which appear to include at least a couple of shots of cats sitting in things. It looks like the Kanizsa square illusion they're referring to is this: <a href="https://puzzlewocky.com/optical-illusions/kanizsa-square-and-triangle-illusions/" rel="nofollow">https://puzzlewocky.com/optical-illusions/kanizsa-square-and...</a>