Short answers, pulled from the story.
The largest recorded egg in the animal kingdom belongs to the whale shark and measures up to 30 centimeters in length. This egg hatches inside the mother rather than being laid externally.
Bird eggshells are composed of calcium carbonate with a 5% organic matrix that allows gas exchange while preventing desiccation and mechanical damage. Tiny pores number around 7000 in a domestic hen's egg and allow the embryo to breathe by exchanging oxygen, carbon dioxide, and water with the surrounding atmosphere.
The vibrant colors of bird eggs result from a complex evolutionary arms race between host species and brood parasites. Pigments like biliverdin and protoporphyrin produce green, blue, red, and brown hues that serve functions from camouflage to signaling male parental care.
The classification of eggs based on yolk content reveals three distinct types: microlecithal eggs with little yolk, mesolecithal eggs with moderate yolk, and macrolecithal eggs with large yolk reserves. These classifications reflect the developmental strategies of different animal groups from direct development to complex larval stages.
The basis of this technology was discovered in 1931 by Alice Miles Woodruff and Ernest William Goodpasture at Vanderbilt University. They found that rickettsia and viruses causing various diseases could grow in chicken embryos.
Laws such as the Protection of Birds Act 1954 and the Wildlife and Countryside Act 1981 in the United Kingdom prohibit the collection and trading of wild bird eggs. These regulations were established to protect rare species and prevent threats to biodiversity.