I do not see it as false advertising, it is simple genetics and some other factors.
There is one gene pair that determines if an egg is base blue or base white. Since Blue is dominant if just one of those two genes at that gene pair is blue, the eggshell will be blue. That part is easy.
A brown or green egg is simply brown pigment on a white based or blue based egg. That's where it gets complicated. There are a lot of different genes that affect the shade of brown. How those different genes get together (if any are even present to begin with) affects the actual shade. Some of those genes are dominant, some recessive, some partially dominant, and some only have an effect if another specific gene is present. That is a big part of the reason you can get so many different shades of brown or green. Those genetics can mix in thousands of different ways.
About the last thing a hen does when laying an egg is to coat it with a liquid we call "bloom". Thye professionals call it cuticle. When it dries it protects against bacteria entering the egg. While mostly clear that liquid can come in different colors or shades. So bloom can affect appearance.
Most of the types of brown pigment go on the egg during the last half hour before it is laid. If for some reason the egg is laid a little early it may not get all of the pigment it normally would so it may be lighter than normal or even white or blue.
This is a simplified version of the science behind the different eggshell colors. While you can look at those photos to see what the eggs might possibly look like no one can guarantee the exact appearance, there are too many variables.
There is one gene pair that determines if an egg is base blue or base white. Since Blue is dominant if just one of those two genes at that gene pair is blue, the eggshell will be blue. That part is easy.
A brown or green egg is simply brown pigment on a white based or blue based egg. That's where it gets complicated. There are a lot of different genes that affect the shade of brown. How those different genes get together (if any are even present to begin with) affects the actual shade. Some of those genes are dominant, some recessive, some partially dominant, and some only have an effect if another specific gene is present. That is a big part of the reason you can get so many different shades of brown or green. Those genetics can mix in thousands of different ways.
About the last thing a hen does when laying an egg is to coat it with a liquid we call "bloom". Thye professionals call it cuticle. When it dries it protects against bacteria entering the egg. While mostly clear that liquid can come in different colors or shades. So bloom can affect appearance.
Most of the types of brown pigment go on the egg during the last half hour before it is laid. If for some reason the egg is laid a little early it may not get all of the pigment it normally would so it may be lighter than normal or even white or blue.
This is a simplified version of the science behind the different eggshell colors. While you can look at those photos to see what the eggs might possibly look like no one can guarantee the exact appearance, there are too many variables.
