Temporal range: 171.6–48.6 Ma
|Egg fossil classification|
|Basic shell type:||†Dinosauroid-spherulitic|
Megaloolithid eggs with multiple layers of eggshell have been preserved in the fossil record. Multilayered fossil eggs resemble those of modern forms in sometimes having incomplete extra layers and pore canals that don't properly align. The misalignment of the pore canals can prevent oxygen from getting to the embryo and cause it to suffocate. The term ovum in ovo has been used for multilayered dinosaur eggs although this is inaccurate use of the term. The greater abundance may indicate that these eggs were more prone to such pathologies, but are most likely due to a larger sample size of them. Megaloolithid eggs with a discretispherulitic morphotype account for the majority of dinosaur eggs preserved with this deformity.
- Mikhailov et al. (1996).
- "Thick Eggshell," Hirsch (2001); page 382.
- "Thick Eggshell," Hirsch (2001); page 383.
- "Thick Eggshell," Hirsch (2001); page 384.
- "Discussion," Hirsch (2001); page 389.
- Kenneth Carpenter, (1999) Eggs, Nests, and Baby Dinosaurs: A Look at Dinosaur Reproduction (Life of the Past), Indiana University Press; ISBN 0-253-33497-7.
- Konstantin E. Mikhailov, Emily S. Bray & Karl E. Hirsch (1996). "Parataxonomy of fossil egg remains (Veterovata): basic principles and applications". Journal of Vertebrate Paleontology. 16 (4): 763–769. doi:10.1080/02724634.1996.10011364. JSTOR 4523773.