I placed the word "eggs" in quotation marks, because maybe they are not eggs... These structures shown in the photos were exposed in a sand dune by the wind in the Negev Desert, Southern Israel. They look calcareous with sand attached to them and they are quite hard and elongated. They are thicker than normal hard-shelled reptile eggs (e.g., geckos, turtles etc). They don't look like soft-shelled reptile eggs, that tear and look like an empty paper bag when they dry out (like Varanus eggs). But the most disturbing character is that they are not round in a cross section, as are all reptile (and bird) eggs that I have seen so far. All of them (found on three different occasions) where flattened in the same way and not round in a cross section.
I will be glad to hear from anyone who has seen something similar elsewhere or has an idea for a process that could lead to form these structures (maybe accumulation of calcium on something else, not necessarily an egg?).
Thanks,
Amos
Thanks Chebaane, but I have seen snake eggs and they are made of pliable, sometimes called leathery shell, and they are soft and flexible, not rigid as those here.
Amos
@ Amos Bouskila , this is looks a like snake egg or any other reptilian, the hardness may be due to some environmental influences.
Thanks. It is true that crocodile eggs are elongated and are indeed hard shelled. Let alone the fact that the last crocodiles in Israel went extinct about 100 years ago, and we never had them in the desert part of the country, the main problem is that they are round in cross section. The mystery "eggs" are all flattened and not round. Contrast the photos I posted above (photographed by Arnon Tsairi, by the way) with croc eggs photo: https://www.tripadvisor.com/LocationPhotoDirectLink-g303998-d457054-i88807168-Crocodile_Farm-Miri_Miri_District_Sarawak.html
Thank you, Abhijit, but there are a few problems in your suggestion - 1. All snakes and most lizards have pliable shelled eggs, and not firm calcareous shells as I described. But even if we consider all those reptiles that do have calcareous egg shells, all of them, as far as I know, are round in a cross-section, and the photos I have attached, especially the small one, demonstrate the oval cross-section, thus it doesn't fit reptiles...
maybe these eggs belong to the species Cerastes cerastes because we can find it in the desert of Palestine**
Thanks, Ameera, but I have seen Cerastes eggs, and they were soft shelled, so could not get the shape and structure of the rigid shells we find in the dunes.
Can they be Uromastyx?
I know that Uromastyx eggs are soft shelled, but is there a possibility that they were buried in sand and dried out, with subsequent calcium deposition? The key question, if reptile egg, where is the dead embyro...unless the embryo never grew.
The fact that they are not fully round can be due to post-depositional compression before they hardened/calcified. with the albumen and yolk undergoing biodecay and the calcified shell surviving....
just a speculation...
https://tilgatenaturecentre.wordpress.com/2013/01/21/2247/
Thank you Dirk,
I know a lot about Uromastyx eggs, as I excavated several natural nests of U. aegyptia during my M.Sc., and checked the temp. conditions, depth of burrow, no. of eggs etc (soon after the hatchlings emerged). It was an amazing journey. Coming back to your suggestion, and leaving aside the doubts that you raised, and the fact we don't know about the process of calcium deposition in inland sand dunes (that have little calcium in them, if at all), the main problem is the lack of Uromastyx lizards in the region where the eggs were found... One can think of eggs of Varanus griseus, that may occur in that region, but still we have to find out about the enigmatic calcification process, the fact that there are no signs of the embryos, the fact that it was found near the surface, while Varanus nests very deep under the ground, and the compression that may have caused the flat cross-section. Pliable eggs shrivel when their volume decreases, not getting flat... Quite a few challenges to comprehend...
Amos Bouskila
with 'Pliable eggs shrivel when their volume decreases' you answered another thought I had to explain the flattish crosssection.
as to the location near the surface: keep in mind (as I am sure you do) that sand dunes move (some of them at least) and many can deflate.
If the inland sand dunes have little calcium then of course in situ calcium deposition on a soft egg is less likely. May I suggest you have a sample 14C dated, which gives you an idea as to age? Get a 3D model done with Reflectance Transformation Imaging or a similar technique before destructive dating
I find your problem fascinating...
Dear Amos,
Is it possible that the absence of Uromastyx from the region where you found the eggs is recent? Those eggs may have been sitting there for a while.
Best,
Marco
Dear Marco
I find the same eggs shell in Sahara ( Libyan desert). I think for beetles
Marco Ferrante
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