Syberchick's Ultimate Rabbit Colors for Dummies Thread inspired me to draw the attached image. All comments and questions are welcome but please bear in mind that the aim is a non-scary introduction, not a completely precise or complete description. If there seems to be a demand for it I intend to add more text on B, E, white spotting etc when I get the time.
I couldn't come up with a good way to fit B in, it is somewhere inside the bottle with the tap and the ear on it.
The idea is that this machine makes rabbit coat colours. When all the parts work normally it makes agouti (also known as chestnut), but sometimes parts are faulty or just completely broken, and then it makes other colours. A rabbit's genes contain blueprints for building the different parts of the machine and errors in the blueprints are responsible for the faulty and broken parts. That said, I'm going to leave the genetics in the background for now and just talk about the machine, I think it is complicated enough just by itself.
The machine in the drawing is loosely based on the actual biological machines responsible for rabbit coat colour but in many places the analogies are not at all accurate. So when I describe a part, the effects on coat colour should be accurate (if a little simplified), but the reasons I give for the physical part working or failing can be very different from the reasons that apply in the actual biological part. I'll mark some of the biggest differences with stars in the text.
There is a copy of this machine at the base of every hair. The alarm A, conveyor D and hairmaker on the right should be pretty self-explanatory. The ear E listens for a noise and switches the attached paintmaker to red if it hears a noise and back to black if it doesnt hear a noise. The power supply C powers the paintmaker**. Red paint is much thicker and gloopier than black paint**, so if there is a minor glitch in the power supply C or the tap is turned halfway off, red paint stops flowing, but black paint is hardly affected.
I'll start with what happens in the parts of an agouti rabbit that show ring colour. When the hair starts growing, the alarm is turned off, so the ear hears nothing and switches the paintmaker to black paint. The paint goes on the conveyor and into the hair, which comes out black. After it has been running for a while, the hairmaker on the right pulls the string, which sounds the alarm. The ear hears the alarm and switches the paintmaker to red paint. The paint goes on the conveyor and into the hair, which comes out red. After the hair has grown a while longer, the hairmaker releases the string, the alarm turns off, the ear hears nothing and switches the paintmaker back to making black paint. At the same time, something (no-one knows what) turns down the tap, so far that the black paint just comes out in a trickle. There isn't enough paint to fully cover the hair, so the base of the hair (next to the skin) comes out grey.
But an agouti rabbit doesn't just have ticking. The nape of the neck is a beautiful red colour and other areas are white (the belly, the underside of the tail, the insides of the ears, circles around the eyes and so on). Why does the machine make these colours? In all these areas, the question mark at the left (again, we dont know what that is) pulls a second string, which is also connected to the alarm, which goes off the whole time, so the ear is always hearing noises and the paintmaker stays on red. In the white areas, in addition to the constant alarm, something fiddles with the tap, turning it down just enough to stop red paint (remember I said that red was thick and gloopy**) but not black paint (this last detail will be important later).
If you've managed to follow all that, then you should be starting to see how to make several other common patterns. If you cut the string across the top* you get tan or otter. If you smash the alarm you get self. If you turn off the power** at C, you get red-eyed-white.
It is less obvious that dilution changes the conveyor D from having lots of small buckets to just a few large ones. The same amount of paint reaches the hair overall, but some parts get too much and some get none at all. The parts with too much don't really get darker (black is still black after all), but the parts with no paint remain white, and from a distance the visual effect of this tiny patchwork paintjob is one of dilution. Black becomes blue-grey and red becomes fawn or cream.
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Edits1&2 2015-03-05 added initial text to go with the diagram and updated the intro accordingly.
I couldn't come up with a good way to fit B in, it is somewhere inside the bottle with the tap and the ear on it.
The idea is that this machine makes rabbit coat colours. When all the parts work normally it makes agouti (also known as chestnut), but sometimes parts are faulty or just completely broken, and then it makes other colours. A rabbit's genes contain blueprints for building the different parts of the machine and errors in the blueprints are responsible for the faulty and broken parts. That said, I'm going to leave the genetics in the background for now and just talk about the machine, I think it is complicated enough just by itself.
The machine in the drawing is loosely based on the actual biological machines responsible for rabbit coat colour but in many places the analogies are not at all accurate. So when I describe a part, the effects on coat colour should be accurate (if a little simplified), but the reasons I give for the physical part working or failing can be very different from the reasons that apply in the actual biological part. I'll mark some of the biggest differences with stars in the text.
There is a copy of this machine at the base of every hair. The alarm A, conveyor D and hairmaker on the right should be pretty self-explanatory. The ear E listens for a noise and switches the attached paintmaker to red if it hears a noise and back to black if it doesnt hear a noise. The power supply C powers the paintmaker**. Red paint is much thicker and gloopier than black paint**, so if there is a minor glitch in the power supply C or the tap is turned halfway off, red paint stops flowing, but black paint is hardly affected.
I'll start with what happens in the parts of an agouti rabbit that show ring colour. When the hair starts growing, the alarm is turned off, so the ear hears nothing and switches the paintmaker to black paint. The paint goes on the conveyor and into the hair, which comes out black. After it has been running for a while, the hairmaker on the right pulls the string, which sounds the alarm. The ear hears the alarm and switches the paintmaker to red paint. The paint goes on the conveyor and into the hair, which comes out red. After the hair has grown a while longer, the hairmaker releases the string, the alarm turns off, the ear hears nothing and switches the paintmaker back to making black paint. At the same time, something (no-one knows what) turns down the tap, so far that the black paint just comes out in a trickle. There isn't enough paint to fully cover the hair, so the base of the hair (next to the skin) comes out grey.
But an agouti rabbit doesn't just have ticking. The nape of the neck is a beautiful red colour and other areas are white (the belly, the underside of the tail, the insides of the ears, circles around the eyes and so on). Why does the machine make these colours? In all these areas, the question mark at the left (again, we dont know what that is) pulls a second string, which is also connected to the alarm, which goes off the whole time, so the ear is always hearing noises and the paintmaker stays on red. In the white areas, in addition to the constant alarm, something fiddles with the tap, turning it down just enough to stop red paint (remember I said that red was thick and gloopy**) but not black paint (this last detail will be important later).
If you've managed to follow all that, then you should be starting to see how to make several other common patterns. If you cut the string across the top* you get tan or otter. If you smash the alarm you get self. If you turn off the power** at C, you get red-eyed-white.
It is less obvious that dilution changes the conveyor D from having lots of small buckets to just a few large ones. The same amount of paint reaches the hair overall, but some parts get too much and some get none at all. The parts with too much don't really get darker (black is still black after all), but the parts with no paint remain white, and from a distance the visual effect of this tiny patchwork paintjob is one of dilution. Black becomes blue-grey and red becomes fawn or cream.
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Edits1&2 2015-03-05 added initial text to go with the diagram and updated the intro accordingly.
