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What is the difference between a white egg and a brown egg?
The difference is that white eggs come from white chickens and brown eggs come from brown chickens. [caution for the humor-impaired: This is not a valid general rule. It only works for a few common breeds. See discussion below.] You think I'm kidding? There are actually different breeds of chickens (just like how there are different breeds of dogs) that lay different colored eggs. The most common breeds of chickens used for egg-laying are the White Leghorn, the Rhode Island Red, and the New Hampshire. White Leghorn chickens are white and lay white eggs. Rhode Island Red and New Hampshire chickens are reddish brown and lay brown or brown-speckled eggs.
Actually, both kinds of eggs start off white. But in the Rhode Island Red and New Hampshire chickens, there is an extra layer of brown coloring on top of the white egg, making it look brown. Nutritionally, there is absolutely no difference between the two types of eggs.
(republished on 07/18/06)
Follow-Up #1: chicken and egg colors?
I breed chickens. Feather color has nothing to do with egg color. Different breeds just lay different egg colors.
- David (age 41)
Augusta, GA, USA
This is way out of the area of knowledge of our current volunteers. In defense of what Tamara (who's now a veterinarian) wrote, an official web site of the egg industry (http://www.incredibleegg.org/egg-facts/eggcyclopedia/c/color
) says "The breed of hen determines the color of the shell. Among commercial breeds, hens with white feathers and ear lobes lay white-shelled eggs; hens with red feathers and ear lobes lay brown eggs.
It sounds like the following statement would be consistent with you, Tamara, and the eggcyclopedia: Over the set of all breeds, there's no consistent relation between feather color and egg color. Within the smaller set of common commercial breeds, there is.
So this doesn't sound like it would meet the usual stringent requirements for a "baloney" item. However, we're leaving it in to encourage more fact-checking of our site.
Thanks for your note.
(published on 07/16/12)
Follow-Up #2: blue and green eggs
If White Eggs come from White Chickens and Brown Eggs come from Brown Chickens, where do the blue and green eggs come from?
Because of the misinformation that you are so willing to share on your website (see http://van.physics.illinois.edu/qa/listing.php?id=19717, as I also raise and breed chickens) I have decided to remove your school from my list of potential colleges to apply to. Thanks for making the decision that much easier.
- Anna (age 26)
Socorro, NM, USA
As any competent physicist knows, blue and green eggs come from the Easter Bunny.
You did read in the last answer that we really don't know anything about this, but just left Tamara's old answer and the critical response up to encourage other readers to look for actual baloney on our site? Did you also read that, so far as we can tell from what other people say, the relation between hen color and egg color only holds for a subset of breeds, although it sounds as if the most common breeds are in that subset? Just to make sure the point isn't missed by the next reader, I've added a caveat to the original answer. Anyway, your response can go up too.
(published on 07/18/12)
Follow-Up #3: a negative review
blah blah blah ....we left this monumental ignorance up to encourage fact checking blah blah blah....
You know, I really don't know much about astrophysics either, but I wouldn't post up some completely factless answer and then make a hugely weak defense of it.
Just makes you look all the more ignorant.
- Mike (age 39)
Seattle, WA, USA
Yeah, speak truth to power... Seriously, we moved an old answer from our own site to the "baloney" category rather than just remove it, to show that we respond to valid criticism. What form of penance would you find more appropriate?
(published on 10/11/12)
Follow-Up #4: eggs again
umm.... sorry could you put the whole egg having to do with the feather color thing into simpler terms; for someone about the junior high age? to Mike W
- katie (age 14)
As nearly as we can tell from reading those sites, each breed has its own egg colors. There are a lot of different types of chickens, and you can find all sorts of different combinations of feather color and egg color. Most chickens used in the big egg production operations are from just a few breeds. It happens that in those few common breeds the white chickens are the ones with white eggs, we're told.
Another interesting animal species is the one that reads and writes this site. Some of us get very worked up about the color of other species feathers. I don't know if anybody knows why.
(published on 05/04/13)
Follow-up on this answer.