There is a widespread meme about "shrimp colors" which hinges on the idea that mantis shimp can see way more colors than us. It turns out this is not true! Mantis shrimp can see ehhh wigglehand, roughly as many colors as humans can.
However, figuring this out required some very interesting science into the mechanics of seeing color, and it paths into the resolution of a second animal-vision myth: cuttlefish are not colorblind, and the explanation for that is even cooler.
Super tl;dr: human vision uses three types of color receptors and make your brain do math to average them out. Mantis shrimp have twelve types of color receptors but don't brain-math so they see slightly fewer colors faster. Cuttlefish don't have color receptors at all and instead use the physics of light refraction (prisms!) to figure out its wavelengths, ie color.

