Cary Woodruff

Phillip and Patricia Frost Museum of Science

The Upper Jurassic Morrison Formation sauropods Diplodocus (formerly “ Seismosaurus ”) hallorum and Supersaurus vivianae are quantifiably the largest dinosaurian taxa from the formation, as well as being among the largest dinosaurs in the world. Their extreme body size (in particular body length, c . 50+ m) has fascinated the paleontological commun...

Headbutting is a combative behavior most popularly portrayed and exemplified in the extant bighorn sheep (Ovis canadensis). When behaviorally proposed in extinct taxa, these organisms are oft depicted Ovis‐like as having used modified cranial structures to combatively slam into one another. The combative behavioral hypothesis of headbutting has a l...

Here we report two new small‐bodied pachycephalosaurines: one from the Dinosaur Park Formation of Alberta and the other from the Hell Creek Formation of Montana, each represented by an isolated squamosal. These two new specimens are approximately the same size as squamosals of Sphaerotholus buchholtzae , and possess several overlapping morphologies...

The Morrison Formation has been explored for dinosaurs for more than 150 years, often specifically for large sauropod skeletons curators wanted to mount as attractions in their museum exhibits around the world. Several long-term campaigns to the Jurassic West of the United States produced hundreds of specimens, ranging from isolated, fragmentary bo...

Other than repaired fractures, osteoarthritis, and periosteal reaction, the vertebrate fossil record has limited evidence of non-osseous diseases. This difficulty in paleontological diagnoses stems from (1) the inability to conduct medical testing, (2) soft-tissue pathologic structures are less likely to be preserved, and (3) many osseous lesions a...

The ontogeny and taxonomy of the dome-headed pachycephalosaurs are topics of continued debate. Pachycephalosaurid diversity in the Maastrichtian of North America is particularly controversial, and the validity and composition within the genus Sphaerotholus remains unresolved. While the type species, S. goodwini, is generally considered valid, debat...

Camarasaurus represents one of the most common dinosaurs from North America, and certainly a contender for one of the most abundantly represented dinosaur taxa worldwide. With numerous specimens ranging the gamut of completeness and maturity, Camarasaurus would theoretically represent a neosauropodian exemplar towards better understanding intra- an...

Many extant invertebrate and vertebrate taxa possess osteological, keratinous, or chitinous structures that are photoluminescent: that is, variably coloured and patterned when observed under ultraviolet light. These features are frequently associated with inter- and/or intraspecific display. Among terrestrial vertebrates, keratinous photoluminescen...

The Morrison Formation has been explored for dinosaurs for more than 150 years, often specifically for largesauropod skeletons curators wanted to mount as attractions in their museum exhibits around the world. Severallong-term campaigns to the Jurassic West of the United States produced hundreds of specimens, ranging fromisolated, fragmentary bones...

The Morrison Formation has been explored for dinosaurs for more than 150 years, often specifically for large sauropod skeletons curators wanted to mount as attractions in their museum exhibits around the world. Several long-term campaigns to the Jurassic West of the United States produced hundreds of specimens, ranging from isolated, fragmentary bo...

Two partial skeletons from Montana represent the northernmost occurrences of Stegosauria within North America. One of these specimens represents the northernmost dinosaur fossil ever recovered from the Morrison Formation. Consisting of fragmentary cranial and postcranial remains, these specimens are contributing to our knowledge of the record and d...

The Morrison Formation has been explored for dinosaurs for more than 150 years, in particular for large sauropod skeletons to be mounted in museum exhibits around the world. Several long-term campaigns to the Jurassic West of the United States produced hundreds of specimens, ranging from isolated, fragmentary bones to nearly complete skeletons of t...

Sauropod dinosaurs were the largest terrestrial vertebrates; yet despite a robust global fossil record, the paucity of cranial remains complicates attempts to understand their paleobiology. An assemblage of small diplodocid sauropods from the Upper Jurassic Morrison Formation of Montana, USA, has produced the smallest diplodocid skull yet discovere...

Stegosauria is a clade of ornithischian dinosaurs characterized by a bizarre array of dermal armor that extends from the neck to the end of the tail. Two genera of stegosaur are currently recognised from North America: the well-known Stegosaurus stenops and the much rarer Hesperosaurus mjosi. A new specimen of Hesperosaurus mjosi was discovered in...

A partial skeleton from the Little Snowy Mountains of central Montana is the first referable specimen of the Morrison Formation macronarian sauropod Camarasaurus. This specimen also represents the northernmost occurrence of a sauropod in the Morrison. Histological study indicates that, although the specimen is relatively small statured, it is skele...

Determining maturity in sauropod dinosaurs histologically is problematic as rapid growth leads to remodeling of Lines of Arrested Growth (LAGs). Although a complimentary system has been devised utilizing several factors including relative amounts of remodeling (Histologic Ontogenetic Stage [HOS]), most assessments of sauropod maturity are based on...

Rugose projections on the anterior and posterior aspects of vertebral neural spines appear throughout Amniota and result from the mineralization of the supraspinous and interspinous ligaments via metaplasia, the process of permanent tissue-type transformation. In mammals , this metaplasia is generally pathological or stress induced, but is a normal...

Within the past decade exceptional preservation of original organic components have been reported from several dinosaurian families, including members of Sauropodomorpha. Here we document the partial preservation of a vertebral ligament in the dorsal and sacral series of a titanosaur. Unlike other cases of tissue preservation, this structure does n...

Historically, sauropods have been largely perceived as having vertical, ‘S’-curved necks which were hypothesised to allow them to feed from the canopy of trees. Within the past two decades, this popular perception has been questioned, resulting in a debate over neck posture. The osteological differences between sauropods with horizontal neck postur...

In the summer of 1878, American paleontologist Edward Drinker Cope published the discovery of a sauropod dinosaur that he named Amphicoelias fragillimus. What distinguishes A. fragillimus in the annals of paleontology is the immense magnitude of the skeletal material. The single incomplete dorsal vertebra as reported by Cope was a meter and a half...

In the summer of 1878, American paleontologist Edward Drinker Cope published the discovery of a sauropod dinosaur that he named Amphicoelias fragillimus. What distinguishes A. fragillimus in the annals of paleontology is the immense magnitude of the skeletal material. The single incomplete dorsal vertebra as reported by Cope was a meter and a half...

Vertebral neural spine bifurcation has been historically treated as largely restrictive to sauropodomorph dinosaurs; wherein it is inferred to be an adaptation in response to the increasing weight from the horizontally extended cervical column. Because no extant terrestrial vertebrates have massive, horizontally extended necks, extant forms with la...

New material representing the northernmost titanosauriform from North America is described from the Cloverly Formation (Aptian/Albian) of Montana, USA. Representing a basal titanosauriform, Rugocaudia cooneyi gen. et sp. nov., the remains consist of 18 caudal vertebral and associated material. Possessing a combination of several unique caudal verte...

Within Diplodocoidea (Dinosauria: Sauropoda), phylogenetic position of the three subclades Rebbachisauridae, Dicraeosauridae, and Diplodocidae is strongly influenced by a relatively small number of characters. Neural spine bifurcation, especially within the cervical vertebrae, is considered to be a derived character, with taxa that lack this featur...

The hypsilophodont Oryctodromeus cubicularis from the Cretaceous Blackleaf Formation of Montana represents the first dinosaur interpreted to be from a burrow fill. The skeletal remains occurred within an incompletely preserved chamber at the end of an S-shaped tunnel. Unlike many fossil vertebrates associated with burrows, the Oryctodromeus remains...