The discovery of pterosaur fossils allows paleontologists to distinguish between the females (left) and males of the species.
A female pterosaur (Darwinopterus) fossil and her egg were found in China, revealing her fractured forearm (arrow). Figure B shows the reptile's sacrum, pelvis and associated egg. (Abbreviations: ip – impression of egg; sc –skull; sk - sacral vertebrae) http://www.msnbc.msn.com/id/4118 ... and_science-science
