Eggs of which species of dinosaurs, reptiles, birds are found at the present time

[MiseriKing]

Hello dear members of the forum.

Very interested in the question of the eggs of which species of dinosaurs are currently found? I mean fossils of course

And why not found eggs suppose stegosaurs or pterosaurs?
Thank you very much.

[Fossildude19]

@CBchiefski  @Troodon @-Andy-  @HamptonsDoc

[Troodon]

Here is a national geographic article on a Pterosaur egg find.

 

https://news.nationalgeographic.com/2017/11/largest-pterosaurs-eggs-discovered-embryos-fossils-paleontology-science/

 

Dinosaur Eggs are typically not associated with species since its unknown what laid them.  Some eggs have been found associated with nests and bones so those eggs can tied to a specific species.  Not aware of anything associated with Stegosaurs.

 

Oviraptor nest from mongolia

[MiseriKing]

Thank you so much. Will read.

But I mean - so many different dinosaurs but not so many eggs...

About stegosaurus - where I can read or know about unidentified eggs, excample Hell creek? Same time interested about eggs in Marocco - so many material and no even eggs shell? just I try find different material and connect together - want make 3d models different nests, but best and complitly what I found - small article in Gregory Paul "The princeton field guide to Dinosaurs"

[HamptonsDoc]

Like Troodon said above, eggs can only be positively attributed to a species if found with embryonic remains or other very convincing evidence, such as in a nesting sight full of juvenile and adult remains but not necessarily embryos.  Confirmed eggs contributed to a specific dino species that I can think of off the top of my head are Oviraptor, Pterosaur, Therizinosaur, Titanosaur, Saltasaurus, and Maiasaur.  There are examples of named turtle and tortoise species attributed to eggs too.  Some paleontologists (Terry Manning) have theorized that dino egg shell is best preserved when laid near brackish water marshes which flooded over nesting sites and buried the nests.  If that theory is correct you can extrapolate why there are so many dino species around and comparatively so few eggs- dinos lived and died in many different environments around the world and not all of them were conducive to preserving shell.

 

The best book I've come across on the topic is Dinosaur Eggs and Babies by Kenneth Carpenter.  Its not an easy read but its full of information about Ootaxons and nesting sites.

[Auspex]

It takes very unusual, very special conditions for eggs to survive fossilization. They are eggs, after all! This is why very few fossil eggs are found.

Unless they found in clear association with an adult skeleton (and not that of a nest robber), or contain a developed, preserved embryo, they must be considered "ichno fossils", just like tracks and other signs.

[mikeymig]

From my collection.

[Auspex]

8 minutes ago, mikeymig said:

From my collection.

 

Bird bones from that formation show similarities to a modern limpkin, but it is better to refer to these as 'from a Limpkin-like bird', as vertebrate species rarely persist for more than 2 million years.

[jpc]

I would say further, that the original paper describing White River eggs looked at three eggs only.  I imagine that there are a few species of eggs represented in the White River.  To be able to say these are "limpkin" like you would have to examine the microscopic eggshell.  That is just my gut feeling.

[PaleoNoel]

About the brackish water theory preserving egg sites better, isn't the two medicine formation an inland environment (was higher in elevation than the Judith River fm). Therefore, there wouldn't be any brackish water in that area to preserve the Maiasaura and other dinosaur eggs preserved in the formation. Maybe that's an exception but it seems to be a glaring one as that's among the best known formations for the preservation of dino eggs.

[mikeymig]

1 hour ago, jpc said:

I would say further, that the original paper describing White River eggs looked at three eggs only.  I imagine that there are a few species of eggs represented in the White River.  To be able to say these are "limpkin" like you would have to examine the microscopic eggshell.  That is just my gut feeling.

I was told it was a duck egg back in 95 when I bought the specimen in Tucson. Then I was told (not gonna mention any names) a few years ago that "most" of the eggs found in the badlands were limpkin not duck. I didnt read a scientific paper or do the microscopic research but It came from a reliable source who knows much about badland/Oligocene fossils. Should I call it "limpkin-like" or just "fossil egg"? Maybe. I want to know what animal I have in my collection and what it may have looked like. So limpkin it is. For now  

[Troodon]

1 hour ago, PaleoNoel said:

About the brackish water theory preserving egg sites better, isn't the two medicine formation an inland environment (was higher in elevation than the Judith River fm). Therefore, there wouldn't be any brackish water in that area to preserve the Maiasaura and other dinosaur eggs preserved in the formation. Maybe that's an exception but it seems to be a glaring one as that's among the best known formations for the preservation of dino eggs.

Paper on TM eggs

https://www.researchgate.net/publication/249023669_Fossil_Eggs_and_Eggshell_from_the_Lowermost_Two_Medicine_Formation_of_Western_Montana_Sevenmile_Hill_Locality

 

 

[Troodon]

8 hours ago, MiseriKing said:

Thank you so much. Will read.

But I mean - so many different dinosaurs but not so many eggs...

About stegosaurus - where I can read or know about unidentified eggs, excample Hell creek? Same time interested about eggs in Marocco - so many material and no even eggs shell? just I try find different material and connect together - want make 3d models different nests, but best and complitly what I found - small article in Gregory Paul "The princeton field guide to Dinosaurs"

Paper on Hell Creek dinosaur egg and eggshells.  I have not heard about any egg material found in Morocco not to say it does not exist.

https://www.researchgate.net/publication/304006752_Fossil_egg_and_eggshells_from_the_Upper_Cretaceous_Hell_Creek_Formation_Montana

 

[jpc]

8 hours ago, mikeymig said:

I was told it was a duck egg back in 95 when I bought the specimen in Tucson. Then I was told (not gonna mention any names) a few years ago that "most" of the eggs found in the badlands were limpkin not duck. I didnt read a scientific paper or do the microscopic research but It came from a reliable source who knows much about badland/Oligocene fossils. Should I call it "limpkin-like" or just "fossil egg"? Maybe. I want to know what animal I have in my collection and what it may have looked like. So limpkin it is. For now  

I simply call them bird eggs.  It would be really fun to redo that paper with as many White River eggs as a feller can find.   

[CBchiefski]

On 5/10/2019 at 1:25 AM, MiseriKing said:

Hello dear members of the forum.

Very interested in the question of the eggs of which species of dinosaurs are currently found? I mean fossils of course

And why not found eggs suppose stegosaurs or pterosaurs?
Thank you very much.

 

On 5/10/2019 at 6:43 AM, MiseriKing said:

Thank you so much. Will read.

But I mean - so many different dinosaurs but not so many eggs...

About stegosaurus - where I can read or know about unidentified eggs, excample Hell creek? Same time interested about eggs in Marocco - so many material and no even eggs shell? just I try find different material and connect together - want make 3d models different nests, but best and complitly what I found - small article in Gregory Paul "The princeton field guide to Dinosaurs"

 

On 5/10/2019 at 1:39 PM, PaleoNoel said:

About the brackish water theory preserving egg sites better, isn't the two medicine formation an inland environment (was higher in elevation than the Judith River fm). Therefore, there wouldn't be any brackish water in that area to preserve the Maiasaura and other dinosaur eggs preserved in the formation. Maybe that's an exception but it seems to be a glaring one as that's among the best known formations for the preservation of dino eggs.

Howdy Miseriking, have you read my advanced dino egg guide?

 

http://www.thefossilforum.com/index.php?/topic/92371-advanced-dinosaur-egg-guide/

 

The paper @Troodon posted is among the best focusing on eggs and eggshell from Hell Creek. There are many explanations purposed for the lack of eggshell in the vast majority of Mesozoic Formations. I lean toward the most simplistic answer, which is eggs and eggshell are relatively easy to destroy especially given millions of years. We know how rare bones, even large ones, are in the fossil record so it is logical to assume eggs and eggshell would be even rarer since they do not preserve as well. As for why certain groups of dinos do not have any eggs yet found, well that a mystery indeed. Their eggs could have been too soft to preserve or perhaps they were laying eggs in sediments which were being eroded away meaning no sediments were deposited to preserve the eggs.

 

Wih pterosaurs not being dinos, they are outside the scope of my research, but I can tell you we have many pterosaur eggs persevered, mostly from China.

 

The Two Med is thought to have potentially brackish water but I have not seen anything to clearly indicate that, such as snails present which live in brackish water. As for eggs and nest, the majority within the Two Med are in mudstone with sandstone as the 2^nd most common. I do think based on the very similar rocks, that nests were constructed in similar environments if not identical ones. A modern example of this would be crocs, most species tend to build their nest a similar distance away from the banks of a river.

Edited May 12, 2019 by CBchiefski
Typo

[Auspex]

On 5/10/2019 at 4:25 PM, mikeymig said:

I want to know what animal I have in my collection and what it may have looked like. So limpkin it is. For now  

Perfectly acceptable! I only replied as I did for the wider audience. it is important to our mission that what is archived here reflects current scientific thinking (and the reasons for it).

 

BTW: the difference in texture between my eggs and yours might suggest different species (or maybe a different preservation). Were I to be naming Ichnospecies, yours and mine would differ (if i couldn't discover a preservational mechanism for the difference).

[-Andy-]

No one really knows why we haven't found Stegosaurus eggs.

 

Stegosaurus fossils are so much rarer than Hadrosaur fossils that it's not entirely surprising that we haven't found their eggs. Yet... we haven't found Triceratops eggs either despite how common Triceratops fossils are.

 

Perhaps it's due to how their nests were constructed. Or just down to sheer, dumb luck. Your guess is as good as mine.

[Auspex]

3 hours ago, -Andy- said:

No one really knows why we haven't found Stegosaurus eggs

How would we know if we had? Without a clear association, it would be a hazardous guess...

[ynot]

On 5/12/2019 at 9:39 AM, -Andy- said:

Perhaps it's due to how their nests were constructed.

I bet they put their nests on the side of cliffs, like puffin do. 

[Mark Kmiecik]

16 hours ago, ynot said:

I bet they put their nests on the side of cliffs, like puffin do. 

Now that IS funny. 

 

On a serious note, though, is it possible that some species may have been livebearers?

[Troodon]

4 hours ago, Mark Kmiecik said:

 

 

On a serious note, though, is it possible that some species may have been livebearers?

Artice from AMNH on that topic.. but most likely no.

 

https://www.amnh.org/dinosaurs/dinosaur-eggs

[Mark Kmiecik]

7 hours ago, Troodon said:

Artice from AMNH on that topic.. but most likely no.

 

https://www.amnh.org/dinosaurs/dinosaur-eggs

So, how large would we speculate that a Giraffatitan egg would be? There are size limitations that would be determined by the ability of an embryo to breathe through the thickness of the shell. Too thin structurally and the eggshell breaks under the weight of just the egg. An egg would have to support its own weight and I'm guessing at least the weight of another egg or two since a creature that size could probably not maneuver its body with enough precision to avoid breaking half the eggs it was laying. Have the eggs of any of the really extra large dinosaurs been found?

[Troodon]

4 hours ago, Mark Kmiecik said:

So, how large would we speculate that a Giraffatitan egg would be? There are size limitations that would be determined by the ability of an embryo to breathe through the thickness of the shell. Too thin structurally and the eggshell breaks under the weight of just the egg. An egg would have to support its own weight and I'm guessing at least the weight of another egg or two since a creature that size could probably not maneuver its body with enough precision to avoid breaking half the eggs it was laying. Have the eggs of any of the really extra large dinosaurs been found?

Have no idea if eggs have ever been found from a Giraffatitan.  Titanosaurid eggs from South America are 7 inches in diameter.