Ray McCarthy
Sentient Marmite: The Truth may make you fret.
At school level they explain that Rods are for sensitive vision at night, we do have more in the periphery, so in Military you are taught to look moving your eyes in a figure of 8 at night, not the central vision.
The colour is from Red, Green and Blue Cones. Well, definitely cones. The problem is that some biologists claimed that no real evidence of pigments existed, that the cones are all identical. One person (ridiculed) claimed that cone spacing caused pairs of cones to respond better to different wavelengths.
Now there is a better explanation.
http://www.bbc.com/news/science-environment-31775458
Guinea pigs are mentioned because unlike dogs and cattle they have very good colour vision.
Two sizes of light pipes is all that's needed, for red and green, the pipe is an already known structure not entirely understood. We do have rods throughout the cone area of the eye.
The eye is most sensitive to the green part of spectrum.
Some people are Tetrachromats (possibly mostly women, just as colour blind are mostly men), but the cornea or lens blocks UV.
Significantly "colour blindness" is most commonly a difference in Red / Green perception not actual monochrome vision (very rare indeed), The blue colour blindness is very rare.
So this idea seems to have some mileage.
The colour is from Red, Green and Blue Cones. Well, definitely cones. The problem is that some biologists claimed that no real evidence of pigments existed, that the cones are all identical. One person (ridiculed) claimed that cone spacing caused pairs of cones to respond better to different wavelengths.
Now there is a better explanation.
http://www.bbc.com/news/science-environment-31775458
Guinea pigs are mentioned because unlike dogs and cattle they have very good colour vision.
Two sizes of light pipes is all that's needed, for red and green, the pipe is an already known structure not entirely understood. We do have rods throughout the cone area of the eye.
The eye is most sensitive to the green part of spectrum.
Some people are Tetrachromats (possibly mostly women, just as colour blind are mostly men), but the cornea or lens blocks UV.
Significantly "colour blindness" is most commonly a difference in Red / Green perception not actual monochrome vision (very rare indeed), The blue colour blindness is very rare.
So this idea seems to have some mileage.
