Color Blindness

In chapter 3 we discussed vision and the possible things that can go wrong with it, such as myopia and presbyopia. This got me thinking about other types of vision problems, and one in particular, color blindness. While meeting up with my one friend recently he declared upon seeing me, "oh hey we have on like the same thing," while gesturing to our shirt colors. He had on a dark blue shirt, whereas mine was purple. I obviously called him out on being an idiot, only to look like a jerk when he told me that he was partially color blind and that is why he made the mistake. Needless to say, I was left feeling a bit confused and thorougly embarassed at my rude remark. This encounter also served to stir my interest in the subject. After researching I found out that color blindess is a result of certain cones misinterpreting wavelengths that correspond to their respective colors. There are also certain types and degrees of color blindness. My friend may have been a mild case, but in some extremely rare cases people are only able to see the world in black and white. There are various tests that are used to detect color blindness. They are composed of dots of colors with a hidden image in the middle. People who are not color blind will have no problem pointing out that they see a certain number or letter within the jumble of colored dots. But for those who are color blind the image will be impossible to see. I also found that color blindness is more common in males than females, and it is usually a genetic trait. The unusual part about it being genetic, however, is that my friend who has it also has a twin brother who is not color blind. Now what are the odds of that happening? But I guess that is a discussion best left for another time.