title: Eggshell and Histology Provide Insight on the Life History of a Pterosaur with Two Functional Ovaries.
abstract: The counterpart of a previously described non-pterodactyloid pterosaur with an egg revealed the presence of a second egg inside the body cavity of this gravid female. It clearly shows that pterosaurs had two functional oviducts and demonstrates that the reduction of one oviduct was not a prerequisite for developing powered flight, at least in this group. Compositional analysis of one egg suggests the lack of a hard external layer of calcium carbonate. Histological sections of one femur lack medullary bone and further demonstrate that this pterosaur reached reproductive maturity before skeletal maturity. This study shows that pterosaurs laid eggs even smaller than previously thought and had a reproductive strategy more similar to basal reptiles than to birds. Whether pterosaurs were highly precocial or needed parental care is still open to debate.
authors.affiliation: Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, CN.
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Wang
authors.affiliation: Museu Nacional, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, BR.
authors.forename: Alexander W A
authors.initials: AW
authors.lastname: Kellner
authors.affiliation: Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, CN.
authors.forename: Xin
authors.initials: X
authors.lastname: Cheng
authors.affiliation: Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, CN.
authors.forename: Shunxing
authors.initials: S
authors.lastname: Jiang
authors.affiliation: Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, CN.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Centro Acadêmico de Vitória, Universidade Federal de Pernambuco, Vitória do Santo Antão, PE, BR.
authors.forename: Juliana M
authors.initials: JM
authors.lastname: Sayão
authors.affiliation: Departamento de Biologia, Centro de Ciências Agrárias, Universidade Federal do Espírito Santo, Alegre, ES, BR.
authors.forename: Taissa
authors.initials: T
authors.lastname: Rodrigues
authors.affiliation: Department of Biological Sciences, Universidade Federal de São Paulo, Diadema, SP, BR.
authors.forename: Fabiana R
authors.initials: FR
authors.lastname: Costa
authors.affiliation: Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, CN.
authors.forename: Ning
authors.initials: N
authors.lastname: Li
authors.affiliation: Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, CN.
authors.forename: X I
authors.initials: XI
authors.lastname: Meng
authors.affiliation: Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, CN.
authors.forename: Zhonghe
authors.initials: Z
authors.lastname: Zhou
mesh_terms: D000818:Animals; D025061:Dinosaurs / Q000033:anatomy & histology / Q000145:classification / Q000502:physiology; D004528:Egg Shell / Q000033:anatomy & histology; D005260:Female; D005580:Fossils; D010053:Ovary / Q000033:anatomy & histology*