Dinosaurs, like other tetrapods, grew more quickly just after hatching than later in life.
However, they did not grow like most other non-avian reptiles, which grow slowly and …

Archosauria originated around the Earth's largest biotic crisis that severely affected all
ecosystems globally, the Permotriassic Mass extinction event, and comprises two crown …

For millions of years, clues to the biology of dinosaurs lie locked within the microscopic
structure of their bones. Here one of the world's leading experts on fossil bone …

Abstract Charles Darwin commented that Ichthyornis, as one of the “toothed birds” from the
Late Cretaceous of Kansas, offered some of “the best support to the theory of evolution”(in …

Long bones (femora, humeri) are the most abundant remains of sauropod dinosaurs. Their
length is a good proxy for body length and body mass, and their histology is informative …

Physiological, anatomical, and developmental features of the crocodilian heart support the
paleontological evidence that the ancestors of living crocodilians were active and …

Identification of the ontogenetic status of an extinct organism is complex, and yet this
underpins major areas of research, from taxonomy and systematics to ecology and …

Studies of soft tissue effects on joint mobility in extant animals can help to constrain
hypotheses about joint mobility in extinct animals. However, joint mobility must be …

Bone microanalyses of extant vertebrates provide a necessary framework from which to form
hypotheses regarding the growth and skeletochronology of extinct taxa. Here, we describe …

Tyrannosaurus rex is the most commonly found North American latest Cretaceous theropod,
but until the 1980s only five specimens had been discovered, and no more than six have …