|MadSci Network: Zoology|
Chickens basically have two types of eggs -- white and brown. Chickens are broken down into four groups: Mediterranean, European, Asian, and American. Only the Mediterranean is white -- and you can tell what color egg a bird will lay by looking at the ear lobe -- it is white in Mediterranean birds and red for all of the other three. (The other colors of the birds are irrelevant.) The white simply represents the absence of pigment production. These birds lost (or never had) this capability. It is important to note that there are no "real" differences between the two types of eggs -- however, if you look very closely at some of the "spots" in the egg white -- those from brown egg birds will be "pigmented" -- so you can tell the egg shell color even in the absence of the shell.
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