Angiosperms first appeared in northern Gondwana during the Early Cretaceous,
approximately 135 million years ago. Several authors have hypothesised that the origin of …

The most commonly cited apomorphy of Archosauriformes is an opening in the snout known
as the antorbital cavity. Despite the ubiquity and prominence of the antorbital cavity, its …

ABSTRACT several attempts have recently been made to recognize synapomorphic
characters of Dinosauria. However, most of the alleged dinosaur synapomorphies show …

The late Cretaceous hadrosaurids were the most specialized and diverse clade of
ornithopod dinosaurs. Parsimony and Bayesian methods were implemented to elucidate the …

Tyrannosaurids are a well-supported clade of very large predatory dinosaurs of Late
Cretaceous Asiamerica. Traditional dinosaurian systematics place these animals within the …

Cretaceous polar dinosaur faunas were taxonomically diverse, which suggests varied
strategies for coping with the climatic stress of high latitudes. Some polar dinosaurs …

Three partial skeletons allow a nearly complete description of the sacrum, pelvic girdle, and
hind limb of the stemsauropodomorph Saturnalia tupiniquim, from the Late Triassic Santa …

Body mass is an important determinant of most biological functions, and knowing the mass
of extinct animals is essential in order to learn about their biology. It was the aim of this …

Several mutually exclusive hypotheses have been advanced to explain the phylogenetic
position of turtles among amniotes. Traditional morphology-based analyses place turtles …

The well-sampled Late Cretaceous fossil record of North America remains the only high-
resolution dataset for evaluating patterns of dinosaur diversity leading up to the terminal …