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Isaac Newton of gravity fame
Thought color and music were much the same.
Do re mi fa so la ti (do),
Seven musical notes, and so
He said ‘Let’s make seven colors too’
Adding orange to red and indigo to blue.

Colors are not black and white

The distinctions between colors are not clear cut.  For convenience, we often talk of Red Orange Yellow Green Blue Indigo Violet (ROY G BIV), as if they are clearly separated (below, left). But, when light is refracted so that we can see the colors, we get a spread of intermingled hues.  The colors grade gently from one to another.  The questions section of the book asks you to find examples of particular colors, and yet any attempt to determine where to set an edge between green and blue (as an example), is doomed to failure.  Add to this,  there are differences among us in how we perceive colors, the most dramatic being color blindness – dealt with on the Ultraviolet page

So,where did the 7 colors of the ROYGBIV spectrum come from?  They came from Isaac Newton.  He was the guy who created the theory of gravity because he noticed that things fell downwards, not sideways nor upwards. He lived from 1642-1727 in England.  He explored how colors were produced when light passed through a glass prism.  He often developed an unscientific, more mystical, explanation of how things were, or how they should be. The number 7 was important to him. It was significant that there are seven musical notes – the do-re-mi-fa-so-la-ti(-do) – and he thought it right that he should divide the spectrum into 7 colors.

If you check out many diagrams of rainbows, you will find that many of them now show only 6 different colors – mostly indigo is absent (the indigone rainbows).  Perhaps we have decided that it is really not very different from blue? 

Indigo pigment from leaves of Indigofera plants
Makes blue jeans from denim pants.
Nature explores all options and makes
Indigo colored buntings, beetles and snakes.

The Indigofera plant is below. It is the plant from which the (indigo) blue pigment used in denim jeans comes from. The indigo bunting (Passerina cyanea) is a small bird that migrates through the United States. Only the male has the blue color, females are more of a brown. There are several types of indigo  beetles, including indigo Volkswagen beetles, but the one we are talking about, Trypocopris vernalis, is found in Europe and Japan. It is a dung beetle that buries dung and carrion as food for young beetle larvae.  The indigo snake, Drymarchon couperi, also called  blue indigo snake, black snake, blue gopher snake, or blue bull snake is found in the south-eastern USA.  The numbers have fallen in recent years, and it is protected in some states, and there are programs to reintroduce it.  There is a different indigo snake in Texas. 

If you have questions, (relevant) thoughts, and more ideas, please let us know below.

Nature Reader colors web Indigo

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