EMBRYOS AND EGGS FOR THE CRETACEOUS THEROPOD DINOSAUR TROODON FORMOSUS

@inproceedings{Varricchio2002EMBRYOSAE,
  title={EMBRYOS AND EGGS FOR THE CRETACEOUS THEROPOD DINOSAUR TROODON FORMOSUS},
  author={David J. Varricchio and John R. Horner and Frankie D. Jackson},
  year={2002}
}
Abstract Elongate and asymmetric eggs of the oospecies Prismatoolithus levis occur regularly in the Upper Cretaceous Two Medicine Formation of western Montana. These eggs had previously been assigned to the ornithischian Orodromeus makelai, for both juvenile and adult remains are typically associated with these eggs. Reexamination of the embryos shows them to exhibit at least 24 apomorphies of the clades Dinosauria, Theropoda and Paraves. The embryos also display a pneumatic quadrate, closely… 
A PHYLOGENETIC ASSESSMENT OF PRISMATIC DINOSAUR EGGS FROM THE CRETACEOUS TWO MEDICINE FORMATION OF MONTANA
TLDR
Cladistic analysis of 14 fossil and extant taxa using 15 egg and shell characters favors a phylogeny consistent with more traditional analyses based on osteologic or genetic data and supports a theropod dinosaur origin for birds.
Elongatoolithid eggs containing oviraptorid (Theropoda, Oviraptorosauria) embryos from the Upper Cretaceous of Southern China
TLDR
The first known oviraptorid embryos associated with pathological eggshells are reported from the Upper Cretaceous Nanxiong Formation of Nankang District, Ganzhou City, Jiangxi Province, China that contain in ovo embryonic skeletons, and the absence of structural and histological abnormalities indicates the environmental factor that led to the eggshell pathologies did not affect the skeletal development of the ovirptorids themselves.
An Early Cretaceous enantiornithine (Aves) preserving an unlaid egg and probable medullary bone
TLDR
The Cretaceous enantiornithine bird Avimaia schweitzerae is described, which preserves an unlaid egg in the abdominal cavity and putative medullary bone, and is hypothesized to represent the ancestral avian condition.
UNIQUE MANIRAPTORAN EGG CLUTCH FROM THE UPPER CRETACEOUS TWO MEDICINE FORMATION OF MONTANA REVEALS THEROPOD NESTING BEHAVIOUR
TLDR
This clutch reveals that the egg-layer of Montanoolithus strongorum had a unique suite of reproductive characteristics and nesting behaviours among maniraptorans.
The first juvenile dromaeosaurid (Dinosauria: Theropoda) from Arctic Alaska
TLDR
This is the first confirmed non-dental fossil specimen from a member of Dromaeosauridae in the Arctic, expanding on the role of Beringia as a dispersal route for this clade between Asia and North America.
Embryos of therizinosauroid theropods from the Upper Cretaceous of China: diagnosis and analysis of ossification patterns
TLDR
Fusion of cervical and caudal neural arches and centra, complete ossification of thoracic ribs and ilium, possible co-ossification of tibia and fibula, fused pubes, complete meta-and acropodial elements, together with small portions of unossified epiphyses of long bones suggest an advanced precociality of these embryos.
An Intermediate Incubation Period and Primitive Brooding in a Theropod Dinosaur
TLDR
This tooth age suggests a Troodon incubation period of 74 days, falling midway between avian and reptilian values predicted by the Troodon egg mass, which concurs with a suite of features in oviraptorosaurs and troodontids that appear dependent upon both adult body and incubation temperatures elevated over ambient conditions.
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