While there is a general correlation between earlobe colour and eggshell colour in chickens, it is not an absolute rule. This is because earlobe colour and eggshell colour are controlled by different genes.

In general, hens with white earlobes typically lay white eggs, while hens with red or dark earlobes typically lay brown eggs. However, there are exceptions to this rule. For example, some breeds of chickens with white earlobes lay brown eggs, and some breeds of chickens with red earlobes lay green or blue eggs.

The reason for this is that the genes that control earlobe colour are located on a different chromosome than the genes that control eggshell colour. This means that the two traits can be inherited independently of each other.

As a result, it is not always possible to accurately predict the colour of a hen's eggs by looking at its earlobes. The most reliable way to determine the colour of a hen's eggs is to simply observe the eggs that she lays.