Spheroolithidae is an

oofamily Egg fossils are the fossilized remains of eggs laid by ancient animals. As evidence of the physiological processes of an animal, egg fossils are considered a type of trace fossil. Under rare circumstances a fossil egg may preserve the remains of t ...

dinosaur egg Dinosaur eggs are the organic vessels in which a dinosaur embryo develops. When the first scientifically documented remains of non-avian dinosaurs were being described in England during the 1820s, it was presumed that dinosaurs had laid eggs bec ...

s. It contains ''

Guegoolithus ''Guegoolithus'' is an oogenus of fossil egg from the early Cretaceous of Spain. It is classified in the oofamily Spheroolithidae, and was probably laid by an ornithopod dinosaur. Distribution ''Guegoolithus'' is known from the Early Cretaceous ...

'', ''

Spheroolithus ''Spheroolithus'' is an oogenus of dinosaur egg.Wang Q, Wang X L, Zhao Z K, and Jiang Y G. (2012).A new oofamily of dinosaur egg from the Upper Cretaceous of Tiantai Basin, Zhejiang Province, and its mechanism of eggshell formation Chinese Scienc ...

'', and '' Paraspheroolithus''. Like modern

birds Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...

, the eggshell membrane formed before the

calcareous Calcareous () is an adjective meaning "mostly or partly composed of calcium carbonate", in other words, containing lime or being chalky. The term is used in a wide variety of scientific disciplines. In zoology ''Calcareous'' is used as an adje ...

part of the shell.Z.-K. Zhao. (1994) "Dinosaur eggs in China:On the structure and evolution of eggshells." In K. Carpenter, K. F. Hirsch, and J. R. Horner (eds.), ''Dinosaur Eggs and Babies,'' Cambridge University Press, Cambridge. Cambridge. pp. 184–203.

References

Egg fossils Dinosaur reproduction {{Dinosaur-stub

See also

References