Evolution of human colour vision other two human opsins. Middle Wavelength Sensitive Opsin (Green-sensitive opsin) – Encoded by the OPN1MW gene with a λmax of 530 found in the green region of the electromagnetic spectrum. Short Wavelength Sensitive Opsin (Blue opsin) – Encoded by the OPN1SW gene with a λmax of 430 found in the blue region of the electromagnetic spectrum. Certain parts of opsin genes and the vision of various species, including humans, has been known to change over time with different environmental changes. Recent studies have shown that primitive nocturnal mammalian ancestors had dichromatic vision consisting of UV–sensitive and red–sensitive traits. A change
Evolution of human colour vision ago and 20 45 million years ago. It eventually reached the current λmax of 430 30 million years ago. It is believed that middle and long wave sensitive pigments appeared after the final stages of short wavelength sensitive opsin pigments evolved, and that trichromatic vision was formed through interprotein epistasis. Scientists believe that the slow rate of evolution of human ancestral vision can also be attributed to slow environmental changes. It has been theorized that -shifts might have been required as human ancestors started to switch from leading nocturnal lifestyles to more diurnal lifestyles. This caused their vision to adjust