Color vision varies significantly across species due to different types and numbers of photoreceptors. Humans are trichromats, meaning we have three types of cone cells that detect red, green, and blue wavelengths. In contrast:
- Dogs are dichromats, seeing primarily blues and yellows
- Birds have tetrachromatic vision, seeing four colors including ultraviolet
- Butterflies can have up to 15 different photoreceptors
Some animals, like most marine mammals, are color-blind and see primarily in grayscale. This variation in color perception is largely due to evolutionary adaptations based on survival needs in different environments.