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soThis page needs a link to the page "Animal_Shell" included somewhere in the text.

Added it to "See also" Adrian J. Hunter 07:03, 16 December 2006 (UTC)Reply[reply]

Could someone please elaborate on how female animals develop eggs within themselves, particularly those that lay hard, calcium-rich shells?

What is the composition of an egg?

In the article, it is suggested that a nice egg is a zygote, thus a cell. Is an egg (like a chicken egg) just a cell, or is it a container that contains one cell and other material to sustain the development of the zygote? The difference between a fertilized egg and an unfertilized

egg yolk and egg white articles suggest that they are the nucleus and the cyotplasm of the cell, up until fertilization, should this be mentioned in this article? Is there a universal structure or composition of eggs, both fertilized and unfertilized? I can't find a diagram of what a (e.g.) chicken egg is made of, and what structures it contains, should such a diagram be added? Anthony Liekens 22:12, 16 October 2005 (UTC)Reply[reply

The german chicken egg article has such a diagram, there is no such article in the Englsih wikipedia. I think such a composition/structure has its place on wikipedia, either here or in
egg (food), which I don't think to be a good place for that. What are your opinions on this? Anthony Liekens 22:22, 16 October 2005 (UTC)Reply[reply

Images and fishy section

a good image to include

OK, well I've cleaned up the page layout of images a little in order to avoid the use of galleries. In the process I removed a couple of the fish images that were less clearly showing eggs themselves. Although we have already got rather more images than text, as Anthony Liekens says above, it would be a good idea to add Image:Ei1.jpg shown right - assuming someone can translate the labelled features.

Of more concern, I started to write the section on fish eggs and fishy reproductive strategies — now, as Sam Cooke might have said, I "don't know much about oology, don't know much ichthyology", so it would be a good idea for someone to check over this section and improve it. In addition there are some interesting things that could be said about parental care of eggs, particularly by cichlids and seahorses. -- Solipsist 09:33, 4 February 2006 (UTC)Reply[reply]

Colors section

I don't have time to do anything with it at the moment, but the whole section on egg coloring needs to be gone over. The overall impression one gets when reading it is that several different authors with widely differing opinions tried to sound like experts on the subject. The section disagrees with itself! EthanL (talk) 12:36, 8 June 2006 (UTC)Reply[reply]


I've removed the following

In reality, the speckles of eggs provide extremely poor camouflague, summed up affectionately by ornithologist Andrew Gosler of the University of Oxford who claimed that "a blind weasel could find them." (see References §)

As it stands, it does not make sense - Gosler himself talks of the strong evolutionary pressure for ground-nesting non-passerines to lay coloured and speckled eggs as camouflage, and anyone who has seen the eggs of species like

Ringed Plover
will have little doubt of the effectiveness of cryptic egg colouration on the bare areas they use for nesting - white eggs would be instantly obvious to any predator in that situation, whereas the cryptic eggs are difficult to see even at close range.

I don't doubt that the quotation is accurate, but there must be something missing from the context, which needs clarification.

OK. it refers only to Great Tits, which are hole-nesters and don't need cryptic eggs. jimfbleak 12:51, 4 July 2006 (UTC)Reply[reply]

jimfbleak 12:30, 4 July 2006 (UTC)Reply[reply]

Egg sizes

Eggs of hummingbird, hen, and ostrich

This image is now available on Commons that might be useful for this article. --Spangineeres (háblame) 02:09, 17 October 2006 (UTC)Reply[reply]

I added it to the gallery. Adrian J. Hunter 14:40, 16 December 2006 (UTC)Reply[reply]


I added a wikify tag. The article seems oddly formated and somewhat incomplete. --Cody.Pope 19:29, 8 November 2006 (UTC)Reply[reply]

I'm not quite sure what it was about the fomatting you didn't like, but I've merged the three very short sections into one, adjusted image layout, and removed an image that didn't make sense without a legend (the image with the caption "a good image to include" on this talk page). I realise including the article title in the heading names is contrary to
WP:MOSHEAD but I think it works on this particular page. So for now I'm removing the wikify tag. Adrian J. Hunter 16:25, 16 December 2006 (UTC)Reply[reply
Also I removed the image of the cowbird eating another bird's egg, since you can't see the cowbird's face or beak from the angle the photo is taken. Adrian J. Hunter 16:25, 16 December 2006 (UTC)Reply[reply]


Why do

Oviparous redirect here if they aren't mentioned in the article? — Omegatron 19:55, 29 December 2006 (UTC)Reply[reply

Oviparous is defined in the third sentence of the lead. Adrian J. Hunter 03:59, 30 December 2006 (UTC)Reply[reply]

A monotreme egg

I would like to ask if anyone could foward more information relating to the monotreme eggs, in what way are they different to reptile and other eggs, an image of an egg, and any other relevant information. Thanks.--Francisco Valverde 15:38, 23 January 2007 (UTC)Reply[reply]

Monotreme eggs are basically similar to reptilian eggs of the same size in internal structure. Also like most reptile eggs, they are semi-soft and easily dry out. Sex determination is genetic rather than temperature dependent. The young is very underdeveloped at hatching, similar to the young of marsupials. Petter Bøckman (talk) 07:56, 31 August 2011 (UTC)Reply[reply]

Very dubious sentence... Hoax!?

The sentence of a feline egg-layer is a certain hoax... --Francisco Valverde 19:06, 29 January 2007 (UTC)Reply[reply]

How does an egg develop?

I presume that before it ends up at 1.5 kg an ostrich egg starts off very much smaller inside the mama ostrich. How does it grow and develop? How does it get the necessary nutrients? And does the shell grow along with the egg, or does it form around the rest of the egg as the final stage of development?

Grendlegrutch 08:34, 18 February 2007 (UTC)Reply[reply]

kinds of eggs

This article is mostly about bird eggs, but arthropods, mollusks, and reptiles have eggs. This article should cover all sorts of eggs, and the bird stuff should go on an "Egg (bird)" page or a "Shelled egg" page. Leadwind 03:43, 9 October 2007 (UTC)Reply[reply]

You are quite right. See the suggested merger of
ovum into this article, discussed below. arkuat (talk) 06:18, 3 June 2008 (UTC)Reply[reply

Please Read

An egg(chicken egg, lizard egg, so on) is just a giant cell, correct? I remember that it is just a giant cell. Can someone here verify/refute this statement. If it's true, please state that an egg is a giant cell in the intro. —Preceding unsigned comment added by MrZhuKeeper (talkcontribs) 18:03, 28 March 2008 (UTC)Reply[reply]

Merge with ovum article?

I'm a little troubled that

egg (bird) redirects here. This is not a good situation. arkuat (talk) 06:27, 3 June 2008 (UTC)Reply[reply

Not merged, but better clarified and differentiated. —Preceding unsigned comment added by (talk) 03:16, 4 June 2008 (UTC)Reply[reply]

Differentiated? But there is no difference between an egg and an ovum in the biological sense. This is just a case of two words meaning the same thing.

egg (biology), I think, ought to be merged arkuat (talk) 05:26, 4 June 2008 (UTC)Reply[reply

Amniote needs to be kept an eye on by any editors undertaking the proposed merge. arkuat (talk) 05:02, 7 June 2008 (UTC)Reply[reply]

I'd like to add a split tag suggesting that part of this article (based on its categorization in Aviculture) should be split to a new article

WP:Split doesn't seem to suggest an easy way to do that. arkuat (talk) 06:53, 9 June 2008 (UTC)Reply[reply

Support, but following the merge the topic would benefit from splitting to form linked pages for "human ovum", "bird egg" to cover ornithology, and perhaps others, which might take a lot of work. Snowman (talk) 11:27, 9 June 2008 (UTC)Reply[reply]

Thanks for the support, Snowman. I'd like to mention that the editors of Eggshell probably ought to be recruited into this effort as well. --arkuat (talk) 06:13, 23 June 2008 (UTC)Reply[reply]

Oppose: This article covers a complete multicellular structure containing a developing embryo; the
ovum article covers unfertilized female megagametes. These are entirely different structures. Although the former does result from fertilization of the latter, the result of that fertilization is the presence of a new organism which was not previously present. --EncycloPetey (talk) 21:16, 27 June 2008 (UTC)Reply[reply

Rotten eggs

I got here from

Hydrogen Sulfide as that article links here via the term "rotten eggs". However this article says nothing about what causes eggs to rot, or what causes the characteristic "rotten egg" smell. If someone knowledgeable could expand the article to cover this it would be most useful Manning (talk) 10:09, 1 June 2009 (UTC)Reply[reply

That article currently implies that the smell is caused by anaerobic bacteria that invade the (otherwise sterile) egg and liberate the sulfur from the amino acids. Probably that article (or a more specific article on the kinds of bacteria) is the best place for section giving a detailed exposition of the topic. Nonetheless, it might be worth very briefly mentioning here somewhere here the degree of sterility (or absence of immune system) of eggs, in a way that directs the reader back to hydrogen sulfide if they want details about rotten eggs. Cesiumfrog (talk) 02:12, 3 April 2012 (UTC)Reply[reply]

Cellular structure

More information on the cellular biology of eggs would be interesting. I have read claims that an unfertilized egg is a single cell, making eggs by far the largest cells in biology. (talk) 06:53, 25 September 2010 (UTC)Reply[reply]

Probably among the most massive, sure. But maybe not the longest; the axons of individual neuron cells can reach from your toe to your head. Cesiumfrog (talk) 02:16, 3 April 2012 (UTC)Reply[reply]

Days til hatched?

There seems to be no general range of time for eggs to hatch. I realize this varies radically, but it seems to me that some general range could be stated. Student7 (talk) 00:05, 19 November 2011 (UTC)Reply[reply]

Have you tried googling for any examples? Cesiumfrog (talk) 02:16, 3 April 2012 (UTC)Reply[reply]
For starters, look up triops. Their eggs can take incredibly long periods between laying and hatching. Cesiumfrog (talk) 06:03, 6 April 2012 (UTC)Reply[reply]

Ambiguous sentence in lead about egg and ovum

The sentence reads:

The term "egg" is used differently outside the animal kingdom, for an egg cell (sometimes called an ovum).

Animal kingdom redirects to Animal, and humans being animals as well, this sentence seems unclear. Also, it appears that in some languages the term egg is often used for ovum, and in others ovum is almost exclusively used for mammals (e.g. in French). If the intent of this sentence is to explain that in biology egg may also be used for ovum and vice-versa, or that mammal eggs may also be referred to as ova, it should probably be reformulated. The current sentence appears to promote the unscientific idea that humans are not animals (perhaps involuntarily). (talk) 03:19, 3 April 2013 (UTC)Reply[reply]

Requested move

The following discussion is an archived discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review. No further edits should be made to this section.

The result of the move request was: move Anthony Appleyard (talk) 16:22, 20 December 2013 (UTC)Reply[reply]

egg (food), that is, eggs prepared as food. I believe that the biological entity is what people are mostly looking for when they type in egg (and exactly that). When people want the food item, they will almost certainly type in "eggs" and not "egg" into the search bar. And I would support "eggs" continuing to redirect to the disambiguation page. But when people type in the word "egg", they are most likely looking for that thing that a mother animal lays. (The egg cell also is a valid potential target, but apart from being only a partial title match, a cursory look at Google Books for the singular word "egg" shows only the shell-bearing eggs. Google News is less useful though far more interesting, as most are using the biological egg in a figurative sense--see this article innovatively titled Man hits sister for being an 'egg'. And I would also support EGG
remaining a redirect to the disambiguation page).

It certainly goes without saying that no other article has any considerable or notable claim to primary topic. Red Slash 03:53, 22 November 2013 (UTC)Reply[reply]

What is the object of the move? - is to misdirect cooks to articles on frogs eggs, is it to make editors mislink cookery articles to the biology article? Can someone explain who exactly benefits from disguising the biology article as a cooking article? In ictu oculi (talk) 16:23, 22 November 2013 (UTC)Reply[reply]
    • Readers benefit,
      Turkey (country)? I'm sure that more than a couple of culinary or avian article writers have accidentally linked to turkey thinking of the bird or its meat, and I'm certain more than a couple readers have searched for the bird and clicked on the country's article forgetting that the country shares its name! Red Slash 21:20, 23 November 2013 (UTC)Reply[reply
As you say, that is an absurd argument.
In this case your only evidence so far that more biologists than cooks use wikipedia is "I believe," you first need to have some evidence for your belief before comparing your belief to an absurd argument.
Still oppose - adding oppose reasons below. In ictu oculi (talk) 00:00, 25 November 2013 (UTC)Reply[reply]
Do forgive me, I saw that you asked twice "what's the point?" and so I answered the question of what the point was. Had you asked "what's the basis" instead, I would have responded using more sources. Do you see those Google Books results? And I'm not going to respond to the absolutely ridiculous suggestion that only biologists use an article on an egg. Clearly they do not. Nor are cooks the only ones who would read the article on the food - that's patently not the point. Red Slash 00:45, 26 November 2013 (UTC)Reply[reply]
Striking second !vote by same participant - this appears to be a restatement of the initial vote, but it is best to avoid the appearance of impropriety. bd2412 T 02:55, 9 December 2013 (UTC)Reply[reply]
  • Oppose Sorry, I don't see anything to choose from between the biological and culinary uses. The only argument I see that really addresses this is "eggs" being more used for the latter, but I think this would just cause confusion. If not for their respective sizes, I'd question why the articles were even separate. I wish there were some way to
    WP:CONCEPTDAB this, because the general topic of eggs is definitely primary. --BDD (talk) 18:19, 22 November 2013 (UTC)Reply[reply
    • Egg (food) is a bit deceptive, because it is really only about eggs as human food. Many animals eat eggs (and some humans eat eggs without cooking them), so really that article could be titled Egg (human cooked food). bd2412 T 21:26, 22 November 2013 (UTC)Reply[reply
Nearly everything made of biological matter is food for something. Category:Foods focuses on human food. In ictu oculi (talk) 23:48, 22 November 2013 (UTC)Reply[reply]
BDD, I don't think you need to apologize! But the Google Books results I gave showed to me that most people who write "egg" mean, well, the thing an oviparous animal lays. As a secondary option, I might want to CONCEPTDAB it, but like you said, these are two huge topics that both deserve extensive Wikipedia articles. Red Slash 21:20, 23 November 2013 (UTC)Reply[reply]
  • Oppose
    ovum, the female gamete or "egg". However, there are many more cookbooks in the world than biology books, so it hardly seems likely that the biological sense is primary over the culinary. -- (talk) 04:37, 23 November 2013 (UTC)Reply[reply
In what way is a zygote commonly referred to as an "egg"? Red Slash 21:20, 23 November 2013 (UTC)Reply[reply]
In human anatomy: a fertilised egg (or
), by cavitation. If an egg is not fertilised, then does not become a zygote. "Egg" and "Zygote" are not the same. 15:00, 24 November 2013 (UTC)
I think I can pretty safely say that the thing a bird or a snake plops out has primary topic for the word "egg" over that. Though I thank you, sincerely, for the excellent explanation. I understand that much better now! smile Red Slash 00:45, 26 November 2013 (UTC)Reply[reply]
  • Support it's bizarre that what everyone thinks of as an "egg" is at a weird thrush (bird) type place. All the other meanings are secondary to the common sense meaning... but this is Wikipedia, so I predict a 50/50 result with no sensible outcome. Jimfbleak - talk to me? 07:04, 23 November 2013 (UTC)Reply[reply]
... But do people think of a an egg for cooking, an egg for hatching, or the gamete. Snowman (talk) 11:50, 25 November 2013 (UTC)Reply[reply]
People also think of bird legs for cooking - why don't we make Leg into a disambiguation page, with subpages for Leg (biology) and Leg (food). Perhaps it is because the legs we eat for food are legs? bd2412 T 16:32, 3 December 2013 (UTC)Reply[reply]
egg (biology) article by typing in the word "egg" will still be just one easy click away from the article on egg cells. Red Slash 00:45, 26 November 2013 (UTC)Reply[reply
...but "Egg (food)" gets many more hits than "Egg (biology)". Snowman (talk) 16:49, 26 November 2013 (UTC)Reply[reply]
...but most people are not getting there by searching egg. Red Slash 23:41, 26 November 2013 (UTC)Reply[reply]
The above discussion is preserved as an archive of a
requested move. Please do not modify it. Subsequent comments should be made in a new section on this talk page or in a move review
. No further edits should be made to this section.

New Introduction

The introduction as I found it confused different taxonomic levels, jumping from the phylum level down to the class level. Instead I give three animal phyla. Also the original intro had paragraphs with several topics. I separated them, and grouped like topics together.

Please let me know your reasons if you feel it necessary to revert this new introduction. Thanks, Nick Beeson (talk) 20:02, 27 May 2014 (UTC)Reply[reply]

Image key

The caption for the lead image states, "(Click on image for key)". However, clicking brings up the Media Viewer, but no key.  --Lambiam 20:09, 2 September 2015 (UTC)Reply[reply]

Aerus and Taglion

On July 27, 2011 this edit introduced the words "aerus" and "taglion" for the big and little ends of the egg, respectively.

These words came up in an English Stackexchange answer, and it seems there is no evidence that these words existed prior to their inclusion in Wikipedia. I have just removed them. If anyone can find nontrivial usage examples, please mention them. --kundor (talk) 06:53, 16 December 2016 (UTC)Reply[reply]

Sounds like someone enjoying a little joke, or just getting very OveRexcited. Chiswick Chap (talk) 09:06, 16 December 2016 (UTC)Reply[reply]
And they appeared in an actual academic paper last year, still. :D Double sharp (talk) 09:46, 30 December 2022 (UTC)Reply[reply]

21:06, 17 March 2018‎ Alexf (talk | contribs)‎ . . (36,385 bytes) (-67)‎ . . (rm irrelevant)

Alexf, what do you mean? --Neptuul (talk) 21:11, 18 March 2018 (UTC)Reply[reply]

The page is about organic eggs, as a means of reproduction. Showing wooden painted eggs for a quasi-religious festival has little to do with this article. -- Alexf(talk) 21:31, 18 March 2018 (UTC)Reply[reply]
Wooden? This are realy eggs, blown out. --Neptuul (talk) 21:42, 18 March 2018 (UTC)Reply[reply]
Did you it misunderstand, didn't you? --Neptuul (talk) 00:05, 20 March 2018 (UTC)Reply[reply]

Expanded "Colleting"

I expanded the section of "Collecting", added more references and citations, did some proofreading and copy editing. Hashininaru (talk) 11:12, 31 March 2018 (UTC)Reply[reply]

Semi-protected edit request on 8 February 2019

The famous Instagram egg isn't mentioned (talk) 15:28, 8 February 2019 (UTC)Reply[reply]

  • Wikipedia articles are not collections of pop culture trivia. GMGtalk 15:30, 8 February 2019 (UTC)Reply[reply]

removed subsection from "human use " section

An article about eggs does not need a subsection regarding consumption of eggs according to Jewish law...i have removed it Firejuggler86 (talk) 22:38, 13 July 2019 (UTC)Reply[reply]

Edit request, 29 September 2019

"Egg collecting was a popular hobby in various contexts, including among the first Australians favored this practice." -- The last three words are redundant. Also, can a civilisation be described as a "context"? (talk) 15:22, 29 September 2019 (UTC)Reply[reply]

 Done GMGtalk 00:59, 30 September 2019 (UTC)Reply[reply]

Bird, reptile and dinosaur eggs

Egg structure related to nesting behaviour.

"We know that most dinosaurs, including the small relatives of birds, such as troodontids and oviraptosaurs, buried their eggs in the ground in nest mounds. ‘Troodon has elongated eggs that are sort of more vertical in the ground, and it seems like only the upper portion of the eggs are exposed. So their eggs are also kind of buried’, Varricchio says. This is more a reptilian trait.

"One difference betweeen the brooding behaviour of modern birds and reptiles is that birds rotate their eggs to balance out heat transfer. Crocodiles and turtles, however, go through a phase of development where if the nest is disturbed and the eggs are rotated, then the embryos die because they naturally adhere to one side of the egg, and turning them over means development doesn’t proceed properly.

"‘Birds on the other hand have little cords of protein called chalazae that allow the embryo to rotate without affecting it inside the egg, so perhaps the buried condition of dinosaur eggs was a representative of a lack of this’, Varriccchio says. ‘Dinosaurs may have been prohibited from nesting in open nests until they had that key feature. So maybe they didn’t have what we think of as a typical bird nest up in the tree – eggs just kind of lying in a cup, or a little saucer of sticks and stuff like that. Maybe they actually had to ensure that they didn’t rotate by implanting them in the ground.’

"Working alongside Frankie Jackson, also of Montana State University, and Darla Zeletinsky of the University of Calgary in Canada, Varricchio has shown that Troodon laid its eggs vertically in mud, half-buried them, and then most likely incubated the exposed parts by sitting on top of them and perhaps fanning feathers over them. …"

Pickrell, John. Flying Dinosaurs: how fearsome reptiles became birds. NewSouth Publishing; Sydney, 2014. pp. 126–127.

Pelagic (talk) 13:25, 18 October 2019 (UTC)Reply[reply]

Move discussion in progress

There is a move discussion in progress on Wikipedia talk:April Fools/April Foools' Day 2020 which affects this page. Please participate on that page and not in this talk page section. Thank you. —RMCD bot 08:35, 1 April 2020 (UTC)Reply[reply]

who invented the first egg

it's not in this page. who invented the egg, was it a fish or a dinosaur or a lizard? I would like to see this info. — Preceding unsigned comment added by (talk) 04:40, 4 October 2020 (UTC)Reply[reply]

"Kwarte" listed at Redirects for discussion

A discussion is taking place to address the redirect Kwarte. The discussion will occur at Wikipedia:Redirects for discussion/Log/2021 November 26#Kwarte until a consensus is reached, and readers of this page are welcome to contribute to the discussion. Certes (talk) 17:02, 26 November 2021 (UTC)Reply[reply]