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
Adaptation (eye) a contrast ratio of 1,000. What enables the wider reach is that the eye adapts its definition of what is black. The eye takes approximately 20–30 minutes to fully adapt from bright sunlight to complete darkness and becomes 10,000 to 1,000,000 times more sensitive than at full daylight. In this process, the eye's perception of color changes as well (this is called the Purkinje effect). However, it takes approximately five minutes for the eye to adapt from darkness to bright sunlight. This is due to cones obtaining more sensitivity when first entering the dark for the first five minutes but