Mind's eye: How fish detect color and brightness with the brain's pineal gland

Jan 17, 2025

We see color because photoreceptor cones in our eyes detect light waves corresponding to red, green, and blue, while dimness or brightness is detected by photoreceptor rods. Many non-mammalian vertebrates like fish, however, are known to detect color and brightness with the pineal gland, which is part of the brain.