Evolution of human colour vision that are found between 450 and 625. Individuals with various forms of colour blindness such as deuteranopia and protanopia are missing human middle wavelength sensitive or long wavelength sensitive opsins. Their minimum wavelength differences are <5 but only at around 500. Protanopes, who are missing long wavelength sensitive cones, are unable to distinguish between colours in the green-yellow-red section of the electromagnetic spectrum. They find yellow, red and orange colours to have much lower brightness when compared to a trichromat. The dimming of these colours can result in confusion in many cases, such as when attempting to identify red traffic
What Is to Be Done? (novel) Is to Be Done?" is one of the sources of inspiration for Rand's thought. For example, the book's main character Lopuhov says "I am not a man to make sacrifices. And indeed there are no such things. One acts in the way that one finds most pleasant." Vladimir Nabokov's final novel in Russian, "The Gift", ridicules "What is to Be Done?" in its fourth chapter. What Is to Be Done? (novel) What Is To Be Done? (; also translated as What Shall We Do? and literally translated as "What To Do?") is an 1863 novel written by the Russian philosopher,