My friend lent me the Eragon series of fantasy fiction books. In it, a boy becomes a Dragon Rider. The premise is that the Rider and the Dragon become mentally one; they live in each other's thoughts. One observation in the third book, Brisingr, caught my attention: when Eragon sees what his dragon sees, the colours look different because the dragon's eyes are physiologically different and so detect different wavelengths. This is realistic: remember that some insects can see beyond our visible range into the ultra-violet. It's details like this that have got me hooked on the series.
A similar issue came up in work I've been doing with the Upper Sixth. Any object that emits electromagnetic radiation in Physics is called a black body. It's a technical term, based on the idea that matt black objects absorb infra-red heat radiation well - so don't wear black clothes on a sunny day. Technically, the Sun is a black body. Black bodies have a characteristic curve like the one shown below.
They emit across a range of wavelengths. The wavelength for peak intensity is fixed by the temperature of the object. The equation under the graph is called Wein's Law. If you put in the surface temperature of the Sun, the wavelength of the peak comes out somewhere in the green/yellow part of the spectrum. That's also the colour for maximum response for your eye - ie why high visibility jackets are the colour they are. It is no surprise really that evolution has resulted in our eyes having a maximum response for the peak of the Sun though.
