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237:, and eventually vomited out of the animal's system. These "stomach stones" tend to range in size from 1 to 6 centimeters. Larger sizes are known but very rare. Sometimes tiny dimples cover the surface of a stomach stone, which can fool observers into thinking they are the pores of an egg. Fossil egg expert Ken Carpenter has described stomach stones as the most egg-like natural objects, noting that they are "the trickiest objects to correctly identify". Calculi are so egg-like that on one occasion a detailed description of a stomach stone misidentified as a fossil egg was published in the scientific literature. Calculi can be distinguished from real egg fossils because when they are broken open, they show the layers of calcium phosphate and the foreign object at the core. Multiple layers of eggshell are known in
1264:, all putative embryos discovered using x-rays have been misidentifications. This is because the use of x-rays to find embryos is conceptually flawed. Embryo bones are incompletely developed and will generally lack their own mineral content, as such the only source of minerals for these bones is the sediment that fills the egg after burial. The fossilized bones will therefore have the same density as the sediment filling the interior of the egg which served as the source for their mineral content and will be poorly visible in an x-ray image. So far the only reliable method for examining embryonic fossils preserved in dinosaur eggs is to physically extract them through means such as acid dissolution.
1203:. Calcite is capable of acting as a polarizing light filter. When a microscopic thin section sample is rotated relative to polarized light it can eventually block all the light and seem opaque. This phenomenon is called extinction. Different varieties of dinosaur eggs with their different calcite crystal structures have different light extinction properties that can be used to identify and distinguish even eggs that seem very similar on the surface. To reconstruct the three-dimensional structures of the shell's pore channels scientists require a series of multiple radial sections.
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gaseous eggshell molecules, which breaks down the molecules in the eggshell and imbues them with a positive charge. A magnetic field then sorts them by mass before they are detected by the spectrometer. One application of mass spectrometry has been to study the isotope ratios of dinosaur eggshell in order to ascertain their diets and living conditions. However this research is complicated by the fact that isotope ratios can be altered post mortem before or during fossilization. Bacterial decomposition can alter
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enough to have found a nest, the number and arrangement of the eggs must be estimated. Excavation must proceed to significant depth since many dinosaur nests include multiple layers of eggs. As the underside of the nest is excavated, it would be covered by material like newspaper, tin foil, or tissue. Afterwards, the entire block is covered in multiple layers of plaster-soaked strips of burlap. When the plaster is dried, the block is undercut the rest of the way and turned over.
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from being cracked. If the water table is high enough dissolved minerals like calcite can percolate through the pores of the eggshell. When the egg is completely filled it can become sturdy enough to withstand the weight of the overlying sediments. Not all fossil egg specimens are of complete specimens, however. Individual pieces of eggshell are much more robust than the entire egg and can be transported intact long distances from where they were originally laid.
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1073:. Since the infilling sediment is their only source of minerals they will be preserved at basically the same density and therefore have poor visibility in the scan. The validity of this issue has been confirmed by performing Cat scans on fossil eggs known to have embryos inside and noting their poor visibility in the scan images. The only truly reliable way to discover a dinosaur embryo is to cut the egg open or dissolve some of its eggshell away.
1069:, all alleged embryos discovered using this method were actually false alarms. Variations in the type of infilling mineral or cement binding the infilling sediment into rock sometimes resemble bones in CAT scan images. Sometimes eggshell fragments that fell back into the egg when it hatched have been mistaken for embryonic bones. The use of CAT scans to search for embryonic remains is actually conceptually flawed since embryonic bones have not yet
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surface left by the insect during the burrow's original excavation. Fossil insect pupae can also resemble eggs. After death and burial, the decomposition of a deceased pupa would leave a gap in the sediment that could be filled with minerals carried by groundwater, forming an egg-like cast. These pseudo-eggs can be recognized by their small size (usually not much longer than a centimeter or two) and lack of an eggshell with its typical anatomy.
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fossils, which can break down amino acids. Another potential source of error is groundwater, which can leach away amino acids. These issues cast doubt as to whether the results these sorts of studies give are reliable as the actual composition of the eggshell's organic material in life. However, studies applying these techniques have made suggestive findings, including amino acid profiles in dinosaur eggs similar to those in modern birds.
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of dinosaurian eggs, proposed by the Soviet paleontologist A. Sochava, was based on grouping eggs by their pore systems. This system was abandoned when it was discovered that different eggs could have very similar pores, but pore systems do play an important role in modern eggshell parataxonomy. The density and width of the pores, combined with the eggshell's thickness can be used to predict the
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forms from crystals radiating outward from an organic core until they touch neighboring mammillae and grow upwards into the next layer. In spherulitic eggs, the eggs of non-theropod dinosaurs, the eggshell units grow upward from their organic cores; the base of each eggshell unit is rounded, but is not a true mammilla because it does not have a distinct ultrastructure from the top of the unit.
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like pores, mammillae, and prismatic or continuous layers, which are not present in concretions. Any given concretion is unlikely to be exactly the same size as any other, so associations of egg-like objects of different sizes are probably not real eggs at all. Concretions can also be far larger than any real egg so an apparently unnaturally large "egg" has probably been misidentified.
302:. Dinosaur eggs range in shape from spherical to highly elongated (some specimens three times longer than they are wide). Some elongated eggs are symmetrical, whereas others have one rounded end and one pointed end (similar to bird eggs). Most elongated eggs were laid by theropods and have an avian-like eggshell, whereas the spherical eggs typically represent non-theropod dinosaurs.
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each species where compared with one another over the course of the study as well as against the fossilized eggs. The results that was retrieved from the experiment was that while sauropods laid smaller eggs in greater amounts each year, dinosaur of the theropod group was revealed to lay larger eggs less frequently over the years, similar to modern birds today.
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used together synergistically to provide a more complete understanding of the specimen under scrutiny. Eggshell specimens best suited for scanning electron microscopy are those recently broken because such a break will usually occur along the plane of the eggshell's calcite crystal lattice. First, a small specimen would be covered with a very thin layer of
241:, but these layers don't go all the way down to its core the way a stomach stone's do. Calculi are often suspiciously intact, unlike fossil eggs, which are usually damaged. Stomach stones also lack distinct shells with their attending structural components like continuous or prismatic layers, mammillae, and pores.
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others remain in solution. Generally, however, a fossilizing egg's shell keeps the same calcite it had in life, which allows scientists to study its original structure millions of years after the developing dinosaur hatched or died. However, eggs can also sometimes be altered after burial. This process is called
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can be used to infer the 3D structure of a fossil egg's interior by compiling images taken of slices through the egg in small regular increments. Scientists have tried to use CAT scans to look for embryo fossils contained inside the egg without having to damage the egg itself by physically extracting
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When the egg is buried deeply enough, the bacteria decomposing it no longer have access to oxygen and need to power their metabolisms with different substances. These physiological changes in the decomposers also alter the local environment in a way that allows certain minerals to be deposited, while
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The formation of fossil eggs begins with the original egg itself. Not all eggs that end up fossilizing experience the death of their embryo beforehand. Fossil eggs with open tops are common and could result from the preservation of eggs that hatched successfully. Dinosaur eggs whose embryos died were
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In all eggs, the embryo must breathe. In egg-laying amniotes (including dinosaurs), pore canals cutting through the eggshell allow gas exchange between the embryo and the outside world. Dinosaur eggshells exhibit a lot of diversity in pore size, density, and shape. One early attempt at classification
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The innermost layer, known as the mammillary layer or the cone layer, is only found in theropod eggs (the prismatic and ornithoid basic types). It is composed of cone-shaped structures called mammillae at the base of each shell unit. Mammillae are the first part of the eggshell to form. Each mammilla
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knives. Scientists must determine at what point to stop cleaning based on their own criteria. If eggs are fully extracted they can be more fully studied individually at the cost of information regarding the spatial relationships between eggs or if the eggs had hatched. Commercial fossil dealers tend
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of a dinosaur's egg. This can provide both information about nesting behavior and about the climate: eggs buried in sediment have higher rates of gas conductance than those laid in the open, and eggs laid in arid environments have lower gas conductance (to prevent water loss) than those laid in more
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Gel electrophoresis is not necessarily a perfect means of discovering the amino acid composition of dinosaur eggshell because sometimes the amount or type of amino acids present could be altered during or after preservation. One potential confounding factor would be the heating of deeply buried egg
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has been credited with groundbreaking work developing this technique. First, the paleontologist must submerge the egg in a very dilute phosphoric acid bath. Since the acid solution can penetrate the egg, every few days the specimen must be soaked in distilled water to prevent the acid from damaging
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Usually the first evidence of fossil dinosaur eggs to be discovered are shell fragments that have eroded away from the original eggs and been transported downhill by the elements. If the source eggs can be found the area must be examined for more unexposed eggs. If the paleontologists are fortunate
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Whether or not hatching was successful, burial would begin with sediments gradually entering any large openings in the shell. Even intact eggs are likely to fill with sediment once they crack under the strain of deep burial. Sometimes, though, fossilization can begin fast enough to prevent the eggs
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In order to test out how allosterics played a part in dinosaur egg size, scientists used modern day animal species such as birds, crocodiles, and tortoises in their experiment. They set the bird group as representing the theropods with the reptiles representing the sauropod group. The laid eggs of
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is used to view dinosaur eggshell under even greater magnification than is possible with light microscopy. However, this does not mean that scanning electron microscopy is necessarily the superior research method. Since both techniques provide differing amounts and types of information they can be
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pattern imposed on the eggshell by the pressure of being buried deeply. If the pressure gets severe enough, sometimes the eggshell's internal microscopic structure can be completely destroyed. Diagenesis can also happen chemically in addition to physically. The chemical conditions of a decomposing
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Sometimes the living or breeding chambers of an insect burrow are so perfectly egg-shaped that even a paleontologist can mistake a natural cast of these chambers for a fossil egg. Insect burrow fossils can sometimes be distinguished from real egg fossils by the presence of "scratch marks" on their
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out of solution. These minerals accumulate in a mass roughly shaped like the region of altered chemistry. Sometimes the mass produced is egg-shaped. Most egg-shaped concretions have uniform interiors, however some form through the accumulation of mineral in layers. These layered concretions can be
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X-ray equipment, like CAT scans, are used to study the interior of fossil eggs. Unlike CAT scans, x-ray imaging condenses the entire interior of the egg into a single two-dimensional image rather than a series of images documenting the interior in three dimensions. X-ray imaging in the context of
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to measure lenses but can also be used by paleontologists to estimate the life size of dinosaur eggs from shell fragments. The instrument can be used to help estimate the size of fossil eggshells by measuring their curved surfaces. Since most eggs aren't perfectly round measurements from multiple
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Unlike most modern eggs, many dinosaur eggs had a rough texture formed by nodes and ridges ornamenting the surface of their shell. This is predominant in
Cretaceous dinosaur eggs, but very rare in eggs from the Jurassic or Triassic. Because of the lack of modern analogues, the purpose of eggshell
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Concretions also generally lack distinct shells, although sometimes they can appear to have them if their outside surfaces have been case-hardened. Since their interiors are softer, erosion can separate the two, creating eggshell pseudofossils. Real egg fossils should preserve eggshell structures
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The second layer is alternately called the prismatic layer, the columnar layer, the continuous layer, the crystalline layer, the cryptoprismatic layer, the palisade layer, the spongy layer, or the single layer. In this layer, the shell units can be distinct, partially fused together, or entirely
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The fine work of cleaning the egg fossils is performed in a laboratory. Preparation usually begins from the underside of the block, which tends to be the best preserved. Because of their fragility, cleaning fossil eggs requires patience and skill. Scientists use delicate instruments like dental
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is a method for determining eggshell composition that uses a device called a mass spectrometer. First, the eggshell sample must be powdered and placed in the mass spectrometer's vacuum chamber. The powder is vaporized by the heat of an intense laser beam. A stream of electrons then bombard the
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Prolatocanaliculate - Pores vary in width throughout their length. Gas exchange water loss rates are variable, so these eggs could have been laid in many different environments. This type is subdivided into foveocanaliculate with larger pore openings, and lagenocanaliculate with narrower pore
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parts of the egg with varying shell curvatures may be needed to get a full idea of the egg's size. Ideally an eggshell fragment being used to estimate the full size of an egg should be more than 3 cm long. Smaller eggshell fragments are better suited to other methods of study, like the
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ornamentation is unknown, but many functions have been proposed. Possibly, they provided extra strength to the eggshell without having pore canals too long for adequate gas exchange. They could also have helped keep substrate away from the pore openings of eggs that were buried, but modern
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The classification of dinosaur eggs is based on the structure of the egg shells viewed in thin section via microscope, although new techniques such as electron backscatter diffraction have been used. There are three main categories of dinosaur eggs: spherulitic (sauropods and
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the embryo before it is even exposed. If embryonic fossil bone is revealed after drying from the water bath, the exposed fossils must be delicately cleaned with fine instruments like needles and paint brushes. The exposed bone is then coated with plastic preservatives like
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crystal units. The basic arrangement and structure of these eggshell units (called the ultrastructure) is used to divide fossil eggs into several basic types, including the spherulitic, prismatic, and ornithoid basic types, which contain dinosaurs. Dinosaur eggs further
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Beach sands were a good place for dinosaurs to lay their eggs because the sand would be effective at absorbing and holding enough heat to incubate the eggs. One ancient beach deposit in northeastern Spain actually preserves about 300,000 fossil dinosaur eggs.
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can be used to expose the microstructure of shell that has been damaged by weathering. Acids are also used to extract embryo skeletons from the egg encasing them. Even fossilized soft tissue like muscle and cartilage as well as fat globules from the original
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is a method for determining eggshell composition that uses X-rays to directly bombard powdered eggshell. Upon impact some of the x-rays will be diffracted at different angles and intensities depending on the specific elements present in the eggshell.
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and has remained almost unchanged ever since. Horizontally cut thin sections are called tangential thin sections while vertically cut thin sections are called radial sections. Regardless of direction, the sample must be abraded by fine-grit
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to protect it from the acid when submerged for another round. The complete process can take months before the whole embryo is revealed. Even then only about 20% of the eggs subjected to the process reveal any embryo fossils at all.
1272:. The sample can then be bombarded by electrons emitted by the same sort of probe used by scanning electron microscopes. Upon impact with the samples x-rays are emitted that can be used to identify the composition of the shell.
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Fossil dinosaur eggshell fragments can be recognized based on three important traits. Their thickness should be roughly uniform, they are usually slightly curved, and their surface is covered in tiny pores. Less frequently, the
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X-rays can be used to chemically analyze dinosaur eggshell. This technique requires pure shell samples, so the fossil must be completely free of its surrounding rock matrix. The shell must then be further cleaned by an
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Norell, M. A.; Clark, J. M.; Dashzeveg, D.; Barsbold, T.; Chiappe, L. M.; Davidson, A. R.; McKenna, M. C.; Novacek, M. J. (1994). "A theropod dinosaur embryo, and the affinities of the
Flaming Cliffs Dinosaur eggs".
233:. Calculus formation is a defense mechanism protecting the ruminant's stomach from damage if it swallows a foreign object while grazing. After ingestion, the object is covered by the same material composing bone,
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Tubocanaliculate - Large diameter pores with funnel-shaped openings on both inner and outer surfaces of the shell. These eggs would have a high gas exchange rate, and therefore were probably buried in humid
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Obliquicanaliculate - These canals cut diagonally through multiple eggshell units instead of going between them like in other pore systems. Obliquicanaliculate pores are only found in a single oogenus:
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is then used to dye the amino acids and make them visible. The bands of amino acids from the dinosaur eggs can then be compared with the banding of samples with known composition for identification.
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even harder to recognize than those with uniform interiors because the layers can resemble egg white and yolk. The yellow of the false yolk comes from minerals like limonite, siderite, and sulfur.
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present in the organic components of dinosaur eggshell. Contact with human skin can contaminate eggs with foreign amino acids, so only untouched eggs can be investigated using this technique.
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Dauphin, Y.; Jaeger, J.J. (1991). "Implications de l'analyse microstructurale et géochimique des œufs de dinosaures de la cairanne (Bassin d'Aix en
Provence, France, Rognacien inférieur)".
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Multicanaliculate - Numerous large, branching, and closely spaced pore canals. They have a high gas exchange rate, so like tubocanaliculate eggs they were probably also buried humid mounds.
1092:. However, the calcite composing the egg can be altered after burial to include significant calcium content. Cathodoluminescence causes calcite altered in this fashion to glow orange.
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Lawver, Daniel R.; Jin, Xingsheng; Jackson, Frankie D.; Wang, Qiongying (2016). "An Avian Egg from the Lower
Cretaceous (Albian) Liangtoutang Formation of Zhejiang Province, China".
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Compactituberculate - The dome-shaped tops of the shell units form a dense covering of nodes on the surface of the eggshell. This type of ornamentation is most commonly seen in
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egg can make it easy for silica to be incorporated into eggshell and damage its structure. When iron-bearing substances alter eggshell it can be obvious because compounds like
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continuous. In some dinosaur eggs, the prismatic layer exhibits squamatic ultrastructure, where the prismatic structure is obscured by a rough texture resembling lizard skin.
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Giant
Dinosaur (theropod) Eggs of the Oogenus Macroelongatoolithus (Elongatoolithidae) from Southeastern Idaho: Taxonomic, Paleobiogeographic, and Reproductive Implications.
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can be used to dissolve the calcite of the eggshell while leaving the shell's organic content intact. The resultant organic residue would be blended and then implanted into
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Angusticanaliculate - Long, narrow, straight pores with low pore density. These eggs would have a low gas exchange rate, and therefore they were typically laid in dry areas.
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Rimocanaliculate - Very narrow slitlike pore canals. This pore system is seen in modern ostriches, so these eggs were laid in open nests, similar to how ostriches do today.
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Since it varies from egg to egg, the texture of an eggshell's ornamentation is useful for classification. Six types of ornamentation were catalogued by
Carpenter in 1999:
1115:. Electricity would then be run through the sample, causing the amino acids to migrate through the gel until they stop at levels determined by their physical properties.
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Dauphin, Y. (1990). "Incidence de l'état diagénétique des coquilles d'oeufs de dinosaures sur la reconnaissance des morphotypes - exemple du Bassin d'Aix en
Provence".
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Ramotuberculate - Irregular chains of nodes, typically found as a transition between the lineartuberculate midsection and dispersituberculate ends of elongated eggs.
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which bury their eggs have smooth eggshells, so this adaptation is not necessary for animals which bury their eggs. Another hypothesis, proposed by R. M. Mellon in
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Deeming, D. C. and M. W. J. Ferguson (eds.) 1991. Egg incubation: its effect on embryonic development in birds and reptiles. Cambridge
University Press, UK. 448pp.
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Many dinosaur eggs have been recovered from sandstone deposits that formed in the ancient dune fields of what are now northern China and
Mongolia. The presence of
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Though rare in non-avian dinosaurs, some theropod eggs and most bird eggs have a third layer (known as the external layer) made up of vertical calcite crystals.
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Mateus, I; Mateus, H; Antunes, MT; Mateus, O; Taquet, P; Ribeiro, V; Manuppella, G (1998). "Upper
Jurassic theropod dinosaur embryos from Lourinhã (Portugal)".
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likely victims of similar causes to those that kill embryos in modern reptile and bird eggs. Typical causes of death include congenital problems, diseases,
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dinosaur research has generally been used to look for evidence of embryonic fossils contained inside the egg. However, as of Kenneth Carpenter's 1999 book
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to be seen. However, there are many kinds of naturally occurring objects which can resemble fossil eggs. These can fool even professional paleontologists.
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de Ricqlès, A.; Mateus, O.; Antunes, M. T.; Taquet, P. (2001). "Histomorphogenesis of embryos of Upper Jurassic theropods from Lourinhã (Portugal)".
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to expose only the bottom of the eggs since the topsides might be damaged by hatching and therefore less visually appealing to potential customers.
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416:, is that the ridges and nodes would have formed pathways for gas to flow across the surface of the eggshell, preventing accumulation of too much
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Paleontologists' knowledge of the structure of dinosaur eggs is limited to the hard shell. However, it can be inferred that dinosaur eggs had an
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by the microstructural aspects of the crystalline structure of the eggshell units and by the type of their pores and their shell ornamentation.
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292:, the three major membranes in modern bird and reptile eggs. Dinosaur eggs vary greatly in size and shape, but even the largest dinosaur eggs (
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which must be converted to the radius in millimeters. Use of the Geneva Lens Measure to estimate the size of a fossil egg was first done by
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Dispersituberculate - Scattered nodes. This ornamentation is seen on the poles of elongated eggs, which may have allowed accumulations CO
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eggs. Egg discoveries continued to mount all over the world, leading to the development of multiple competing classification schemes.
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can be used to magnify the structure of dinosaur eggshell for scientific research. To do so an eggshell fragment must be embedded in
149:; he thought, however, that they were laid by giant birds. The first scientifically recognized dinosaur egg fossils were discovered
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are formed when decaying organisms change the chemistry of their immediate surroundings in a manner that is conducive to minerals
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Carpenter, Kenneth; Hirsch, Karl; Horner, John (1994). "Introduction". In Carpenter, Kenneth; Hirsch, Karl; Horner, John (eds.).
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preserved in their life brooding position suggests that the eggs, nests, and parents may have been rapidly buried by sandstorms.
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Moratalla, J.J.; Powell, J.E. (1994). "Dinosaur Nesting Patterns". In Carpenter, Kenneth; Hirsch, Karl; Horner, John (eds.).
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1227:. The electrons bounce back off the metal and due to their small size, can be used to form a detailed image of the specimen.
1841:"Combined Use of Electron and Light Microscopy Techniques Reveals False Secondary Shell Units in Megaloolithidae Eggshells"
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Moreno-Azanza, Miguel; Bauluz, Blanca; Canudo, José Ignacio; Gasca, José Manuel; Fernández-Baldor, Fidel Torcida (2016).
2331:"Correction: A comparative embryological study of two ornithischian dinosaurs," Horner and Weishampel (1996); page 103.
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embryo develops. When the first scientifically documented remains of non-avian dinosaurs were being described in
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Dauphin, Y. (1990). "Comparative microstructural studies of eggshells. 1. Dinosaurs of the Southern France".
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Lineartuberculate - Ridges, and chains of ridges and nodes form lines parallel to the long axis of the egg.
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are taxonomic names for types of eggshell. Nearly three dozen oogenera have been named for dinosaur eggs:
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In 1859, the first scientifically documented dinosaur egg fossils were discovered in southern France by a
190:. Sometimes the embryo had absorbed so much of the calcium that the mammillae need a magnifying glass or
1802:"First sauropod (Dinosauria: Saurischia) remains from the Guichón Formation, Late Cretaceous of Uruguay"
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Sagenotuberculate - The nodes and ridges form a netlike pattern interspersed with pits and grooves.
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The first scientifically recognized non-avian dinosaur egg fossils were discovered in 1923 by an
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Anastomotuberculate - Ridges similar to lineartuberculate, but instead form wavy, branching, or
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1789:. The Pitt Building, Trumpington Street, Cambridge: Cambridge University Press. pp. 37–46.
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Reisz, Robert R.; Scott, Diane; Sues, Hans-Dieter; Evans, David C.; Raath, Michael A. (2005).
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Paleontologist and fossil egg expert Kenneth Carpenter catalogued six types of pore systems:
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1689:"Late Cretaceous Dinosaur Eggshells from the Tremp Basin, Southern Pyrenees, Lleida, Spain"
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1199:. The calcite crystal structure of dinosaur eggshell can be classified by their effect on
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Dinosaur eggshells are divided into one, two, or three layers of distinct ultrastructure.
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2738:"Embryos of an Early Jurassic prosauropod dinosaur and their evolutionary significance"
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55:. In 1859, the first scientifically documented dinosaur egg fossils were discovered in
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Dinosaur embryos, the animal inside the eggs, are very rare but useful to understand
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in Mongolia. These eggs were mistakenly attributed to the locally abundant herbivore
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from being buried too deep, inimical temperatures, or too much or too little water.
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Eggs, Nests, and Baby Dinosaurs: A Look at Dinosaur Reproduction (Life of the Past)
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Eggs, Nests, and Baby Dinosaurs: A Look at Dinosaur Reproduction (Life of the Past)
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Eggs, Nests, and Baby Dinosaurs: A Look at Dinosaur Reproduction (Life of the Past)
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in fossil eggshell has been altered. Calcite in eggshell is either pure or rich in
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deposited at these sites are therefore excellent sources of dinosaur egg fossils.
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Fossil dinosaur eggshells, like modern bird and reptile eggshells, are made up of
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2654:"A comparative embryological study of two ornithischian dinosaurs - a correction"
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is the most important tool paleontologists have for revealing whether or not the
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1899:"Basic Types Eggshell: Spherulitic Basic Type," Carpenter (1999); pages 136-137.
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Mikhailov, Konstantin (1996). "Bird Eggs in the Upper Cretaceous of Mongolia".
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563:
535:
497:
409:
305:
299:
294:
285:
272:
The erosive effects of water can sometimes round rocks into egg-like shapes.
251:
163:
48:
2764:
2156:"A new type of dinosaur eggs from Early Cretaceous of Gansu Province, China"
3225:
3185:
3175:
3110:
3097:
2772:
2283:
1886:
1175:
1070:
1045:
938:
812:
654:
619:
598:
528:
513:
454:
158:
79:
183:
3365:
3360:
3355:
3190:
3180:
3145:
3130:
3125:
3047:
2977:
1908:"Basic Types Eggshell: Prismatic Basic Type," Carpenter (1999); page 137.
1741:. Trumpington Street, Cambridge: University of Cambridge. pp. 1–11.
1244:
1188:
1184:
1135:
is a device used to measure curved surfaces. It is most commonly used by
1104:
1023:
963:
953:
909:
816:
507:
468:
401:
247:
3303:
3273:
3263:
3230:
3215:
3120:
2933:
1625:
1180:
976:
921:
825:
738:
518:
201:
Fossilized dinosaur egg from the Gobi desert, National Museum in Prague
191:
83:
3235:
3205:
3155:
3073:
3042:
3032:
3022:
3002:
2923:
2678:
2653:
2634:, Jefferson, North Carolina: McFarland & Company, Inc., pp.
2154:
Xie, J.-F.; Zhang, S.-K.; Jin, X.-S.; Li, D.-Q.; Zhou, L.-Q. (2016).
1224:
1136:
1061:
1001:
983:
949:
Dinosaur eggs are known from a variety of depositional environments.
874:
839:
493:
476:
289:
214:
187:
169:
87:
60:
40:
1761:
Laura E. Wilson, Karen Chin, Frankie D. Jackson, and Emily S. Bray.
1680:
1561:
Laura E. Wilson, Karen Chin, Frankie D. Jackson, and Emily S. Bray.
3313:
3170:
3165:
3160:
3078:
2982:
2913:
1845:
1220:
1145:
1032:
969:
930:
881:
808:
75:
52:
26:
2496:
https://embryo.asu.edu/pages/acid-dissolution-fossil-dinosaur-eggs
122:
3343:
3323:
3240:
3087:
3017:
3007:
1192:
1085:
1065:
them. However, as of Ken Carpenter's 1999 book on dinosaur eggs,
888:
487:
44:
186:
underside of the eggshell fragment will preserve bumps known as
3318:
3288:
3195:
3150:
3052:
2997:
2987:
2848:
1005:
934:
397:
281:
218:
95:
56:
21:
1838:
3012:
2706:
2204:
2202:
1658:" (Doctoral dissertation, Montana State University, Bozeman).
1167:
1164:
1149:
230:
64:
59:
by Jean-Jacques Poech, although they were mistaken for giant
2252:
968:
Dinosaurs often laid their eggs on ancient floodplains. The
98:
inside. The oldest known dinosaur eggs and embryos are from
94:. Sometimes the egg preserves the remains of the developing
3068:
2390:"How to Fossilize an Egg," Carpenter (1999); pages 114–115.
1520:. Bloomington, Indiana: Indiana University Press. pp.
1464:. Bloomington, Indiana: Indiana University Press. pp.
1216:
1108:
1035:
can be uncovered using this method. Amateur paleontologist
1027:
1022:
Acids can be used to learn more about fossil eggs. Diluted
222:
91:
2789:"ROM Puts Oldest Dinosaur Eggs Ever Discovered on Display"
2199:
1686:
1314:"ROM Puts Oldest Dinosaur Eggs Ever Discovered on Display"
1174:. This basic method was invented by French paleontologist
47:
during the 1820s, it was presumed that dinosaurs had laid
3200:
2890:
2686:
1893:
1112:
502:
226:
2701:"Eggs with the Oldest Known Embryos of a Dinosaur Found"
1514:
Carpenter, Kenneth (1999). "How to Study a Fossil Egg".
1334:"Eggs with the Oldest Known Embryos of a Dinosaur Found"
2859:
2437:
213:
Calculi are egg-like objects formed in the stomachs of
2507:"Tools of the Trade," Carpenter (1999); pages 128–130.
2430:
2428:
2426:
2420:"How to Fossilize an Egg," Carpenter (1999); page 110.
2411:"How to Fossilize an Egg," Carpenter (1999); page 111.
2399:"How to Fossilize an Egg," Carpenter (1999); page 115.
2384:
2381:"How to Fossilize an Egg," Carpenter (1999); page 114.
2369:"How to Fossilize an Egg," Carpenter (1999); page 108.
2357:"How to Fossilize an Egg," Carpenter (1999); page 113.
2343:"How to Fossilize an Egg," Carpenter (1999); page 112.
1687:
Vianey-Liaud, Monique; Lopez-Martinez, Nieves (1997).
86:. The interior of a dinosaur egg can be studied using
2407:
2405:
2377:
2375:
2365:
2363:
2353:
2351:
2349:
2339:
2337:
1736:
1362:
1360:
2829:
2709:
Comptes Rendus de l'Académie des Sciences, Série IIA
2510:
2088:
2735:
2446:
2443:"Collecting Eggs," Carpenter (1999); pages 117–118.
2423:
1902:
457:
patterns resembling the water ripple marks in sand.
67:were not yet recognized as dinosaurs at the time).
2501:
2414:
2402:
2393:
2372:
2360:
2346:
2334:
1357:
1170:and sliced into a thin section with a thin-bladed
2595:"Tools of the Trade," Carpenter (1999); page 132.
2586:"Tools of the Trade," Carpenter (1999); page 131.
2577:"Tools of the Trade," Carpenter (1999); page 125.
2573:
2571:
2565:"Tools of the Trade," Carpenter (1999); page 124.
2556:"Tools of the Trade," Carpenter (1999); page 122.
2552:
2550:
2544:"Tools of the Trade," Carpenter (1999); page 134.
2540:
2538:
2532:"Tools of the Trade," Carpenter (1999); page 133.
2528:
2526:
2524:
2522:
2486:"Tools of the Trade," Carpenter (1999); page 130.
2482:
2480:
2478:
2476:
2470:"Tools of the Trade," Carpenter (1999); page 128.
2466:
2464:
2462:
2460:
2458:
2325:
2082:
1799:
1433:
1412:
3410:
2651:
1509:
1507:
1505:
1453:
1451:
1449:
1447:
1445:
1426:
1424:
2307:
1784:
1503:
1501:
1499:
1497:
1495:
1493:
1491:
1489:
1487:
1485:
1405:
1403:
1401:
1399:
1397:
1395:
1393:
1383:
1381:
1206:
423:and aiding the flow of oxygen and water vapor.
90:or by gradually dissolving away the shell with
2652:Horner, John R.; Weishampel, David B. (1996).
2589:
2580:
2568:
2559:
2547:
2535:
2519:
2473:
2455:
2452:"Collecting Eggs," Carpenter (1999); page 118.
2434:"Collecting Eggs," Carpenter (1999); page 117.
2147:
1366:"Collecting Eggs," Carpenter (1999); page 115.
1354:"First Discoveries," Carpenter (1999); page 4.
1345:"First Discoveries," Carpenter (1999); page 5.
1303:"First Discoveries," Carpenter (1999); page 1.
2875:
2153:
1611:
1442:
1439:"Fake Eggs," Carpenter (1999); pages 119–120.
1421:
1418:"Fake Eggs," Carpenter (1999); pages 120–121.
990:
941:can turn the shell blackish or rusty colors.
2298:
1800:Soto, M.; Perea, D.; Cambiaso, A.V. (2012).
1482:
1458:Carpenter, Kenneth (1999). "Making an Egg".
1390:
1378:
1369:
1223:. The specimen would then be bombarded with
944:
2689:Memórias da Academia das Ciências de Lisboa
2632:Dinosaurs: The Encyclopedia. 3rd Supplement
2316:
1348:
1339:
1297:
2882:
2868:
2322:"Abstract," Reisz et al. (2005); page 761.
1648:
1103:has been used in attempts to identify the
924:. One form of diagenesis is a microscopic
2677:
1954:
1876:
1866:
1667:
1513:
1457:
1326:
1144:. The Geneva Lens measure gives units in
444:at the poles to escape between the nodes.
1952:
1950:
1948:
1946:
1944:
1942:
1940:
1938:
1936:
1934:
1911:
1806:Journal of South American Earth Sciences
1780:
1778:
1776:
1774:
1430:"Fake Eggs," Carpenter (1999); page 119.
1409:"Fake Eggs," Carpenter (1999); page 120.
1387:"Fake Eggs," Carpenter (1999); page 121.
1375:"Fake Eggs," Carpenter (1999); page 118.
492:
304:
196:
121:
20:
2516:"Fig 7.11," Carpenter (1999); page 118.
1853:(5) (published May 4, 2016): e0153026.
1596:
1577:
1557:
1555:
1553:
1551:
1549:
1547:
1545:
1543:
1541:
3411:
1306:
1126:
1095:
1076:
1012:
78:. Dinosaur eggshell can be studied in
16:Vessel for dinosaur embryo development
2863:
1931:
1771:
1767:UCMP Online Exhibits: Fossil Eggshell
1755:
1730:
1661:
1567:UCMP Online Exhibits: Fossil Eggshell
1563:II. Eggshell morphology and structure
3391:
2807:University of Bristol Earth Sciences
2628:"Appendix: Dinosaur Tracks and Eggs"
2625:
1793:
1538:
1230:
1191:. Then the structure of the shell's
145:and amateur naturalist named Father
1155:
1017:
319:
157:crew while looking for evidence of
39:are the organic vessels in which a
13:
2091:Journal of Vertebrate Paleontology
309:Diagram of a two-layered eggshell.
155:American Museum of Natural History
133:egg with preserved embryo, at the
72:American Museum of Natural History
14:
3440:
2825:
2798:. insidetoronto.com. May 6, 2010.
1323:. insidetoronto.com. May 6, 2010.
1195:or pores can be examined under a
819:. Embryo fossils are known from:
461:
176:
3390:
3379:
3378:
2847:
2832:
390:
31:Indroda Dinosaur and Fossil Park
2489:
2246:
2235:
2224:
2213:
2188:
2136:
2125:
2071:
2060:
2049:
2038:
2027:
2016:
2005:
1994:
1983:
1972:
1961:
1832:
1605:
1590:
1571:
1262:Eggs, Nests, and Baby Dinosaurs
1067:Eggs, Nests, and Baby Dinosaurs
118:Timeline of egg fossil research
108:, about 190 million years ago.
2703:. BBC News. November 12, 2010.
1336:. BBC News. November 12, 2010.
344:
1:
2729:10.1016/s1251-8050(01)01580-4
2601:
2111:10.1080/02724634.2016.1100631
205:
2611:, Indiana University Press;
2276:10.1126/science.266.5186.779
1868:10.1371/journal.pone.0153026
1826:10.1016/j.jsames.2011.08.003
1614:Paläontologische Zeitschrift
1291:
1212:Scanning electron microscopy
1207:Scanning electron microscopy
1056:
896:
275:
7:
2607:Carpenter, Kenneth (1999).
482:
479:, including modern birds).
10:
3445:
2242:The Palaeobiology Database
2231:The Palaeobiology Database
2220:The Palaeobiology Database
2209:The Palaeobiology Database
2195:The Palaeobiology Database
2143:The Palaeobiology Database
2132:The Palaeobiology Database
2078:The Palaeobiology Database
2067:The Palaeobiology Database
2056:The Palaeobiology Database
2045:The Palaeobiology Database
2034:The Palaeobiology Database
2023:The Palaeobiology Database
2012:The Palaeobiology Database
2001:The Palaeobiology Database
1990:The Palaeobiology Database
1979:The Palaeobiology Database
1968:The Palaeobiology Database
991:Excavation and preparation
900:
802:
167:, but are now known to be
115:
111:
3374:
3249:
3096:
3061:
2970:
2932:
2906:
2897:
2803:"What are dinosaur eggs?"
2313:de Ricqles et al. (2001).
2169:(1): 1–10. Archived from
1716:10.1017/s002233600003609x
1254:
945:Depositional environments
325:
104:, which lived during the
2889:
2626:Glut, Donald F. (2003),
1787:Dinosaur Eggs and Babies
1763:V. Paleobiology and eggs
1739:Dinosaur Eggs and Babies
1601:. sér/ II, 310: 849–954.
1152:on fossil ostrich eggs.
2765:10.1126/science.1114942
1920:What are dinosaur eggs?
1696:Journal of Paleontology
1670:Paleontological Journal
1197:petrographic microscope
1142:Obrig radius dial gauge
3424:Dinosaur trace fossils
2163:Vertebrata PalAsiatica
1654:Simon, D. J. (2014). "
1599:C. R. Acad. Sci. Paris
1580:Revue de Paléobiologie
1000:picks, needles, small
522:
310:
202:
138:
33:
3429:Dinosaur reproduction
2794:May 10, 2010, at the
2304:Mateus et al. (1998).
1319:May 10, 2010, at the
1004:engraving tools, and
753:Spheruprismatoolithus
578:Dispersituberoolithus
496:
308:
263:Insect trace fossils:
200:
125:
24:
3284:Egg drop competition
2856:at Wikimedia Commons
1251:ratios of eggshell.
1117:Protein silver stain
627:Macroelongatoolithus
414:Princeton University
2813:on February 1, 2014
2757:2005Sci...309..761R
2721:2001CRASE.332..647D
2670:1996Natur.383..103H
2268:1994Sci...266..779N
2176:on January 29, 2016
2103:2016JVPal..36E0631L
1927:on February 1, 2014
1859:2016PLoSO..1153026M
1818:2012JSAES..33...68S
1708:1997JPal...71.1157V
1243:ratios in eggs and
1133:Geneva Lens Measure
1127:Geneva lens measure
1101:Gel electrophoresis
1096:Gel electrophoresis
1082:Cathodoluminescence
1077:Cathodoluminescence
1013:Research techniques
718:Protoceratopsidovum
147:Jean-Jacques Pouech
82:and viewed under a
3279:Egg-and-spoon race
3106:List of egg dishes
2919:Fish and amphibian
2900:List of egg topics
2699:Moskvitch, Katia.
1626:10.1007/bf02989853
1332:Moskvitch, Katia.
788:Tristraguloolithus
725:Pseudogeckoolithus
704:Preprismatoolithus
523:
383:Preprismatoolithus
355:humid conditions.
311:
203:
139:
51:because they were
34:
29:eggs displayed at
3406:
3405:
3339:Ovo vegetarianism
2852:Media related to
2751:(5735): 761–764.
2664:(6595): 256–257.
2645:978-0-7864-1166-5
2262:(5186): 779–782.
1748:978-0-521-44342-5
1531:978-0-253-33497-8
1475:978-0-253-33497-8
1276:X-ray diffraction
1236:Mass spectrometry
1231:Mass spectrometry
1090:calcium carbonate
690:Porituberoolithus
669:Paraspheroolithus
662:Pachycorioolithus
641:Nanshiungoolithus
475:, and ornithoid (
315:calcium carbonate
239:pathological eggs
235:calcium phosphate
3436:
3394:
3393:
3382:
3381:
3136:Custard desserts
2884:
2877:
2870:
2861:
2860:
2851:
2842:
2840:Dinosaurs portal
2837:
2836:
2835:
2821:
2820:
2818:
2809:, archived from
2787:Skinner, Justin.
2784:
2742:
2732:
2696:
2683:
2681:
2679:10.1038/383103b0
2648:
2596:
2593:
2587:
2584:
2578:
2575:
2566:
2563:
2557:
2554:
2545:
2542:
2533:
2530:
2517:
2514:
2508:
2505:
2499:
2493:
2487:
2484:
2471:
2468:
2453:
2450:
2444:
2441:
2435:
2432:
2421:
2418:
2412:
2409:
2400:
2397:
2391:
2388:
2382:
2379:
2370:
2367:
2358:
2355:
2344:
2341:
2332:
2329:
2323:
2320:
2314:
2311:
2305:
2302:
2296:
2295:
2250:
2244:
2239:
2233:
2228:
2222:
2217:
2211:
2206:
2197:
2192:
2186:
2185:
2183:
2181:
2175:
2160:
2151:
2145:
2140:
2134:
2129:
2123:
2122:
2086:
2080:
2075:
2069:
2064:
2058:
2053:
2047:
2042:
2036:
2031:
2025:
2020:
2014:
2009:
2003:
1998:
1992:
1987:
1981:
1976:
1970:
1965:
1959:
1956:
1929:
1928:
1923:, archived from
1915:
1909:
1906:
1900:
1897:
1891:
1890:
1880:
1870:
1836:
1830:
1829:
1797:
1791:
1790:
1782:
1769:
1759:
1753:
1752:
1734:
1728:
1727:
1702:(6): 1157–1171.
1693:
1684:
1678:
1677:
1665:
1659:
1652:
1646:
1645:
1620:(3–4): 391–404.
1609:
1603:
1602:
1594:
1588:
1587:
1575:
1569:
1559:
1536:
1535:
1511:
1480:
1479:
1455:
1440:
1437:
1431:
1428:
1419:
1416:
1410:
1407:
1388:
1385:
1376:
1373:
1367:
1364:
1355:
1352:
1346:
1343:
1337:
1330:
1324:
1312:Skinner, Justin.
1310:
1304:
1301:
1193:calcite crystals
1161:Light microscopy
1156:Light microscopy
1018:Acid dissolution
861:Lourinhanosaurus
697:Polyclonoolithus
3444:
3443:
3439:
3438:
3437:
3435:
3434:
3433:
3409:
3408:
3407:
3402:
3370:
3245:
3092:
3057:
2993:Ichthyoplankton
2966:
2928:
2902:
2893:
2888:
2854:Dinosauria eggs
2838:
2833:
2831:
2828:
2816:
2814:
2801:
2796:Wayback Machine
2740:
2715:(10): 647–656.
2646:
2604:
2599:
2594:
2590:
2585:
2581:
2576:
2569:
2564:
2560:
2555:
2548:
2543:
2536:
2531:
2520:
2515:
2511:
2506:
2502:
2494:
2490:
2485:
2474:
2469:
2456:
2451:
2447:
2442:
2438:
2433:
2424:
2419:
2415:
2410:
2403:
2398:
2394:
2389:
2385:
2380:
2373:
2368:
2361:
2356:
2347:
2342:
2335:
2330:
2326:
2321:
2317:
2312:
2308:
2303:
2299:
2251:
2247:
2240:
2236:
2229:
2225:
2218:
2214:
2207:
2200:
2193:
2189:
2179:
2177:
2173:
2158:
2152:
2148:
2141:
2137:
2130:
2126:
2097:(3): e1100631.
2087:
2083:
2076:
2072:
2065:
2061:
2054:
2050:
2043:
2039:
2032:
2028:
2021:
2017:
2010:
2006:
1999:
1995:
1988:
1984:
1977:
1973:
1966:
1962:
1957:
1932:
1917:
1916:
1912:
1907:
1903:
1898:
1894:
1837:
1833:
1798:
1794:
1783:
1772:
1760:
1756:
1749:
1735:
1731:
1691:
1685:
1681:
1666:
1662:
1653:
1649:
1610:
1606:
1595:
1591:
1576:
1572:
1560:
1539:
1532:
1512:
1483:
1476:
1456:
1443:
1438:
1434:
1429:
1422:
1417:
1413:
1408:
1391:
1386:
1379:
1374:
1370:
1365:
1358:
1353:
1349:
1344:
1340:
1331:
1327:
1321:Wayback Machine
1311:
1307:
1302:
1298:
1294:
1270:ultrasonic bath
1257:
1233:
1209:
1201:polarized light
1158:
1129:
1098:
1079:
1059:
1020:
1015:
993:
947:
905:
899:
894:
815:, and dinosaur
805:
800:
760:Stromatoolithus
732:Shixingoolithus
711:Prismatoolithus
606:Heishanoolithus
592:Elongatoolithus
557:Continuoolithus
500:nest and eggs (
485:
464:
443:
421:
393:
352:gas conductance
347:
328:
278:
208:
179:
151:serendipitously
143:Catholic priest
120:
114:
17:
12:
11:
5:
3442:
3432:
3431:
3426:
3421:
3404:
3403:
3401:
3400:
3388:
3375:
3372:
3371:
3369:
3368:
3363:
3358:
3353:
3352:
3351:
3349:Vegreville egg
3341:
3336:
3331:
3326:
3321:
3316:
3311:
3306:
3301:
3296:
3291:
3286:
3281:
3276:
3271:
3266:
3261:
3255:
3253:
3247:
3246:
3244:
3243:
3238:
3233:
3228:
3223:
3218:
3213:
3208:
3203:
3198:
3193:
3188:
3183:
3178:
3173:
3168:
3163:
3158:
3153:
3148:
3143:
3138:
3133:
3128:
3123:
3118:
3113:
3108:
3102:
3100:
3094:
3093:
3091:
3090:
3085:
3076:
3071:
3065:
3063:
3059:
3058:
3056:
3055:
3050:
3045:
3040:
3035:
3030:
3025:
3020:
3015:
3010:
3005:
3000:
2995:
2990:
2985:
2980:
2974:
2972:
2968:
2967:
2965:
2964:
2959:
2949:
2944:
2938:
2936:
2930:
2929:
2927:
2926:
2921:
2916:
2910:
2908:
2904:
2903:
2898:
2895:
2894:
2887:
2886:
2879:
2872:
2864:
2858:
2857:
2844:
2843:
2827:
2826:External links
2824:
2823:
2822:
2799:
2785:
2733:
2704:
2697:
2684:
2649:
2644:
2623:
2620:
2603:
2600:
2598:
2597:
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2579:
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2534:
2518:
2509:
2500:
2498:Last paragraph
2488:
2472:
2454:
2445:
2436:
2422:
2413:
2401:
2392:
2383:
2371:
2359:
2345:
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2297:
2245:
2234:
2223:
2212:
2198:
2187:
2146:
2135:
2124:
2081:
2070:
2059:
2048:
2037:
2026:
2015:
2004:
1993:
1982:
1971:
1960:
1930:
1910:
1901:
1892:
1831:
1792:
1770:
1754:
1747:
1729:
1679:
1660:
1647:
1604:
1589:
1570:
1537:
1530:
1481:
1474:
1441:
1432:
1420:
1411:
1389:
1377:
1368:
1356:
1347:
1338:
1325:
1305:
1295:
1293:
1290:
1256:
1253:
1249:oxygen isotope
1247:can alter the
1241:carbon isotope
1232:
1229:
1208:
1205:
1157:
1154:
1128:
1125:
1097:
1094:
1078:
1075:
1058:
1055:
1019:
1016:
1014:
1011:
992:
989:
946:
943:
901:Main article:
898:
895:
893:
892:
885:
878:
871:
868:Massospondylus
864:
857:
850:
843:
836:
829:
821:
804:
801:
799:
798:
791:
784:
777:
770:
767:Subtiliolithus
763:
756:
749:
742:
735:
728:
721:
714:
707:
700:
693:
686:
679:
676:Phaceloolithus
672:
665:
658:
651:
648:Oblongoolithus
644:
637:
630:
623:
616:
613:Laevisoolithus
609:
602:
595:
588:
585:Ellipsoolithus
581:
574:
567:
560:
553:
550:Cairanoolithus
546:
543:Boletuoolithus
539:
532:
524:
484:
481:
463:
462:Classification
460:
459:
458:
451:
448:
445:
441:
438:
435:
432:megaloolithids
419:
392:
389:
388:
387:
377:
374:
370:
367:
363:
346:
343:
327:
324:
277:
274:
207:
204:
178:
177:Identification
175:
153:in 1923 by an
116:Main article:
113:
110:
106:Early Jurassic
101:Massospondylus
15:
9:
6:
4:
3:
2:
3441:
3430:
3427:
3425:
3422:
3420:
3417:
3416:
3414:
3399:
3398:
3389:
3387:
3386:
3377:
3376:
3373:
3367:
3364:
3362:
3359:
3357:
3354:
3350:
3347:
3346:
3345:
3342:
3340:
3337:
3335:
3334:Organizations
3332:
3330:
3327:
3325:
3322:
3320:
3317:
3315:
3312:
3310:
3309:Humpty Dumpty
3307:
3305:
3302:
3300:
3297:
3295:
3292:
3290:
3287:
3285:
3282:
3280:
3277:
3275:
3272:
3270:
3267:
3265:
3262:
3260:
3257:
3256:
3254:
3252:
3248:
3242:
3239:
3237:
3234:
3232:
3229:
3227:
3224:
3222:
3219:
3217:
3214:
3212:
3209:
3207:
3204:
3202:
3199:
3197:
3194:
3192:
3189:
3187:
3184:
3182:
3179:
3177:
3174:
3172:
3169:
3167:
3164:
3162:
3159:
3157:
3154:
3152:
3149:
3147:
3144:
3142:
3139:
3137:
3134:
3132:
3129:
3127:
3124:
3122:
3119:
3117:
3114:
3112:
3109:
3107:
3104:
3103:
3101:
3099:
3095:
3089:
3086:
3084:
3080:
3077:
3075:
3072:
3070:
3067:
3066:
3064:
3060:
3054:
3051:
3049:
3046:
3044:
3041:
3039:
3036:
3034:
3031:
3029:
3028:Ovoviviparity
3026:
3024:
3021:
3019:
3016:
3014:
3011:
3009:
3006:
3004:
3001:
2999:
2996:
2994:
2991:
2989:
2986:
2984:
2981:
2979:
2976:
2975:
2973:
2969:
2963:
2960:
2957:
2953:
2950:
2948:
2945:
2943:
2940:
2939:
2937:
2935:
2934:Fossil record
2931:
2925:
2922:
2920:
2917:
2915:
2912:
2911:
2909:
2905:
2901:
2896:
2892:
2885:
2880:
2878:
2873:
2871:
2866:
2865:
2862:
2855:
2850:
2846:
2845:
2841:
2830:
2812:
2808:
2804:
2800:
2797:
2793:
2790:
2786:
2782:
2778:
2774:
2770:
2766:
2762:
2758:
2754:
2750:
2746:
2739:
2734:
2730:
2726:
2722:
2718:
2714:
2710:
2705:
2702:
2698:
2694:
2690:
2685:
2680:
2675:
2671:
2667:
2663:
2659:
2655:
2650:
2647:
2641:
2637:
2633:
2629:
2624:
2621:
2618:
2617:0-253-33497-7
2614:
2610:
2606:
2605:
2592:
2583:
2574:
2572:
2562:
2553:
2551:
2541:
2539:
2529:
2527:
2525:
2523:
2513:
2504:
2497:
2492:
2483:
2481:
2479:
2477:
2467:
2465:
2463:
2461:
2459:
2449:
2440:
2431:
2429:
2427:
2417:
2408:
2406:
2396:
2387:
2378:
2376:
2366:
2364:
2354:
2352:
2350:
2340:
2338:
2328:
2319:
2310:
2301:
2293:
2289:
2285:
2281:
2277:
2273:
2269:
2265:
2261:
2257:
2249:
2243:
2238:
2232:
2227:
2221:
2216:
2210:
2205:
2203:
2196:
2191:
2172:
2168:
2164:
2157:
2150:
2144:
2139:
2133:
2128:
2120:
2116:
2112:
2108:
2104:
2100:
2096:
2092:
2085:
2079:
2074:
2068:
2063:
2057:
2052:
2046:
2041:
2035:
2030:
2024:
2019:
2013:
2008:
2002:
1997:
1991:
1986:
1980:
1975:
1969:
1964:
1955:
1953:
1951:
1949:
1947:
1945:
1943:
1941:
1939:
1937:
1935:
1926:
1922:
1921:
1914:
1905:
1896:
1888:
1884:
1879:
1874:
1869:
1864:
1860:
1856:
1852:
1848:
1847:
1842:
1835:
1827:
1823:
1819:
1815:
1811:
1807:
1803:
1796:
1788:
1781:
1779:
1777:
1775:
1768:
1764:
1758:
1750:
1744:
1740:
1733:
1725:
1721:
1717:
1713:
1709:
1705:
1701:
1697:
1690:
1683:
1676:(1): 114–116.
1675:
1671:
1664:
1657:
1651:
1643:
1639:
1635:
1631:
1627:
1623:
1619:
1615:
1608:
1600:
1593:
1585:
1581:
1574:
1568:
1564:
1558:
1556:
1554:
1552:
1550:
1548:
1546:
1544:
1542:
1533:
1527:
1523:
1519:
1518:
1510:
1508:
1506:
1504:
1502:
1500:
1498:
1496:
1494:
1492:
1490:
1488:
1486:
1477:
1471:
1467:
1463:
1462:
1454:
1452:
1450:
1448:
1446:
1436:
1427:
1425:
1415:
1406:
1404:
1402:
1400:
1398:
1396:
1394:
1384:
1382:
1372:
1363:
1361:
1351:
1342:
1335:
1329:
1322:
1318:
1315:
1309:
1300:
1296:
1289:
1285:
1284:
1280:
1277:
1273:
1271:
1265:
1263:
1252:
1250:
1246:
1242:
1237:
1228:
1226:
1222:
1218:
1213:
1204:
1202:
1198:
1194:
1190:
1186:
1182:
1177:
1173:
1169:
1166:
1162:
1153:
1151:
1147:
1143:
1138:
1134:
1124:
1120:
1118:
1114:
1110:
1106:
1102:
1093:
1091:
1087:
1083:
1074:
1072:
1068:
1063:
1054:
1051:
1047:
1043:
1038:
1037:Terry Manning
1034:
1029:
1025:
1010:
1007:
1003:
997:
988:
986:
985:
980:
978:
973:
971:
967:
965:
960:
957:
955:
950:
942:
940:
936:
932:
927:
926:cross-hatched
923:
917:
913:
911:
904:
903:Egg taphonomy
891:
890:
886:
883:
879:
877:
876:
872:
870:
869:
865:
863:
862:
858:
856:
855:
854:Lufengosaurus
851:
848:
847:Hypacrosaurus
844:
842:
841:
837:
835:
834:
830:
828:
827:
823:
822:
820:
818:
814:
810:
797:
796:
795:Youngoolithus
792:
790:
789:
785:
783:
782:
781:Trachoolithus
778:
776:
775:
774:Tacuarembovum
771:
769:
768:
764:
762:
761:
757:
755:
754:
750:
748:
747:
746:Spheroolithus
743:
741:
740:
736:
734:
733:
729:
727:
726:
722:
720:
719:
715:
713:
712:
708:
706:
705:
701:
699:
698:
694:
692:
691:
687:
685:
684:
680:
678:
677:
673:
671:
670:
666:
664:
663:
659:
657:
656:
652:
650:
649:
645:
643:
642:
638:
636:
635:
634:Megaloolithus
631:
629:
628:
624:
622:
621:
617:
615:
614:
610:
608:
607:
603:
601:
600:
596:
594:
593:
589:
587:
586:
582:
580:
579:
575:
573:
572:
571:Dictyoolithus
568:
566:
565:
564:Dendroolithus
561:
559:
558:
554:
552:
551:
547:
545:
544:
540:
538:
537:
536:Apheloolithus
533:
531:
530:
526:
525:
520:
516:
515:
510:
509:
505:
504:
499:
498:Therizinosaur
495:
491:
489:
480:
478:
474:
470:
456:
452:
449:
446:
439:
436:
433:
429:
428:
427:
424:
422:
415:
411:
410:senior thesis
407:
403:
399:
391:Ornamentation
385:
384:
378:
375:
371:
368:
364:
361:
360:
359:
356:
353:
342:
339:
335:
331:
323:
321:
316:
307:
303:
301:
300:elephant bird
297:
296:
295:Megaloolithus
291:
287:
283:
273:
271:
267:
264:
260:
256:
253:
252:precipitating
249:
246:
242:
240:
236:
232:
228:
224:
220:
216:
212:
199:
195:
193:
189:
185:
174:
172:
171:
166:
165:
164:Protoceratops
160:
156:
152:
148:
144:
136:
132:
130:
124:
119:
109:
107:
103:
102:
97:
93:
89:
85:
81:
77:
73:
68:
66:
62:
58:
54:
50:
46:
42:
38:
37:Dinosaur eggs
32:
28:
23:
19:
3395:
3383:
3176:Onsen tamago
2955:
2815:, retrieved
2811:the original
2806:
2748:
2744:
2712:
2708:
2692:
2688:
2661:
2657:
2631:
2608:
2591:
2582:
2561:
2512:
2503:
2491:
2448:
2439:
2416:
2395:
2386:
2327:
2318:
2309:
2300:
2259:
2255:
2248:
2237:
2226:
2215:
2190:
2178:. Retrieved
2171:the original
2166:
2162:
2149:
2138:
2127:
2094:
2090:
2084:
2073:
2062:
2051:
2040:
2029:
2018:
2007:
1996:
1985:
1974:
1963:
1958:Glut (2003).
1925:the original
1919:
1913:
1904:
1895:
1850:
1844:
1834:
1812:(1): 68–79.
1809:
1805:
1795:
1786:
1766:
1757:
1738:
1732:
1699:
1695:
1682:
1673:
1669:
1663:
1650:
1617:
1613:
1607:
1598:
1592:
1583:
1579:
1573:
1566:
1516:
1460:
1435:
1414:
1371:
1350:
1341:
1328:
1308:
1299:
1286:
1282:
1281:
1274:
1266:
1261:
1258:
1234:
1210:
1187:until it is
1176:Paul Gervais
1159:
1130:
1121:
1099:
1080:
1066:
1060:
1046:Paraloid B72
1042:Acryloid B67
1021:
998:
994:
982:
975:
974:
962:
961:
952:
951:
948:
939:iron sulfide
918:
914:
906:
887:
873:
866:
859:
852:
838:
831:
824:
813:heterochrony
806:
793:
786:
779:
772:
765:
758:
751:
744:
737:
730:
723:
716:
709:
702:
695:
688:
683:Placoolithus
681:
674:
667:
660:
655:Ovaloolithus
653:
646:
639:
632:
625:
620:Macroolithus
618:
611:
604:
599:Faveoolithus
597:
590:
583:
576:
569:
562:
555:
548:
541:
534:
529:Ageroolithus
527:
514:Dinosaurland
512:
506:
501:
486:
465:
455:anastomosing
425:
402:crocodylians
394:
381:
357:
348:
340:
336:
332:
329:
312:
293:
279:
269:
268:
262:
261:
257:
245:Concretions:
244:
243:
210:
209:
180:
168:
162:
159:early humans
140:
127:
99:
80:thin section
69:
36:
35:
18:
3294:Fabergé egg
2180:January 11,
1283:Allosterics
1245:groundwater
1189:translucent
1185:emery paper
1105:amino acids
1071:mineralized
1024:acetic acid
964:Floodplains
954:Beach sands
910:suffocation
817:systematics
508:Segnosaurus
345:Pore canals
248:Concretions
25:Fossilized
3413:Categories
3304:HowToBasic
3299:Free range
3274:Easter egg
3269:Decorating
3251:In culture
3141:Deep fried
3062:Components
2942:Cephalopod
2695:: 101–110.
2602:References
1586:: 127–133.
977:Sand dunes
922:diagenesis
826:Beibeilong
739:Sphaerovum
521:, England.
519:Lyme Regis
511:) in from
469:hadrosaurs
320:classified
206:False eggs
192:microscope
84:microscope
3259:Balancing
3221:Scrambled
3033:Ovulation
3023:Oviparity
3003:Oogenesis
2962:Pathology
2924:Monotreme
1724:131405598
1642:129041143
1634:0031-0220
1292:Footnotes
1225:electrons
1137:opticians
1062:CAT scans
1057:CAT scans
1050:Vinac B15
1002:pneumatic
984:Oviraptor
970:mudstones
897:Taphonomy
875:Maiasaura
840:Heyuannia
477:theropods
473:prismatic
373:openings.
290:allantois
288:, and an
276:Structure
215:ruminants
211:Calculus:
188:mammillae
170:Oviraptor
131:osmolskae
88:CAT scans
61:bird eggs
3385:Category
3186:Powdered
3171:Omelette
3166:Meringue
3116:Benedict
3083:membrane
2983:Egg cell
2956:dinosaur
2817:June 20,
2792:Archived
2781:37548361
2773:16051793
2292:22333224
2284:17730398
2119:88169746
1887:27144767
1846:PLOS ONE
1317:Archived
1221:platinum
1172:rock saw
1146:diopters
1033:egg yolk
931:hematite
882:Qianlong
833:Citipati
809:ontogeny
488:Oogenera
483:Oogenera
217:such as
129:Citipati
76:Mongolia
74:crew in
53:reptiles
41:dinosaur
27:sauropod
3397:Commons
3366:Tossing
3361:Tapping
3356:Rolling
3344:Pysanka
3329:Organic
3324:Oomancy
3236:Soufflé
3226:Shirred
3191:Pickled
3181:Poached
3146:Deviled
3131:Coddled
3126:Century
3098:As food
3088:Chalaza
3048:Trophic
3018:Oviduct
3008:Ootheca
2978:Allergy
2971:Biology
2952:Reptile
2753:Bibcode
2745:Science
2717:Bibcode
2666:Bibcode
2636:613–652
2264:Bibcode
2256:Science
2099:Bibcode
1878:4856302
1855:Bibcode
1814:Bibcode
1704:Bibcode
1522:122–144
1086:calcium
889:Troodon
803:Embryos
408:in his
398:turtles
366:mounds.
286:chorion
270:Stones:
184:concave
112:History
45:England
3319:Oology
3289:Egging
3264:Carton
3231:Smoked
3216:Scotch
3211:Salted
3196:Quiche
3151:Eggnog
3121:Boiled
3053:Zygote
2998:Oogamy
2988:Embryo
2779:
2771:
2658:Nature
2642:
2615:
2290:
2282:
2117:
1885:
1875:
1745:
1722:
1640:
1632:
1528:
1472:
1466:85–107
1255:X rays
1006:X-Acto
937:, and
935:pyrite
326:Layers
282:amnion
229:, and
219:cattle
96:embryo
57:France
3206:Salad
3156:Fried
3111:Balut
3079:Shell
3074:White
3043:Tooth
3038:Spawn
3013:Ovary
2907:Types
2777:S2CID
2741:(PDF)
2288:S2CID
2174:(PDF)
2159:(PDF)
2115:S2CID
1720:S2CID
1692:(PDF)
1638:S2CID
1168:resin
1165:epoxy
1150:Sauer
1048:, or
231:goats
65:birds
3419:Eggs
3314:Hunt
3161:Iron
3081:and
3069:Yolk
2947:Fish
2914:Bird
2891:Eggs
2819:2013
2769:PMID
2640:ISBN
2613:ISBN
2280:PMID
2182:2016
1883:PMID
1743:ISBN
1630:ISSN
1526:ISBN
1470:ISBN
1217:gold
1181:sand
1131:The
1109:EDTA
1028:EDTA
406:1982
400:and
223:deer
135:AMNH
92:acid
49:eggs
3241:Tea
3201:Roe
2761:doi
2749:309
2725:doi
2713:332
2674:doi
2662:383
2272:doi
2260:266
2107:doi
1873:PMC
1863:doi
1822:doi
1712:doi
1622:doi
1219:or
1183:or
1113:gel
1026:or
517:in
503:cf.
471:),
412:at
227:elk
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