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Small, Speedy Plant-Eater Extends Knowledge of Dinosaur Ecosystems

By Guest PostMay 24, 2013Nature, Sciencealbertadromeus syntarsus, canada, cleveland museum, david evans, dinosaur diversity, dinosaur ecosystems, duckbilled dinosaurs, ecological community, journal, knowledge, late cretaceous, michael ryan, natural history, new dinosaur, North America, ornithopod cousins, paleontologist, rabbits, royal ontario museum, small dinosaurs, southern alberta, speedy plant eater, t rex, university of calgary, university of toronto, vertebrate paleontology

Bethesda, MD — Dinosaurs are often thought of as large, fierce animals, but new research highlights a previously overlooked diversity of small dinosaurs. In the Journal of Vertebrate Paleontology, a team of paleontologists from the University of Toronto, Royal Ontario Museum, Cleveland Museum of Natural History and University of Calgary have described a new dinosaur, the smallest plant-eating dinosaur species known from Canada. Albertadromeus syntarsus was identified from a partial hind leg, and other skeletal elements, that indicate it was a speedy runner. Approximately 1.6 m (5 ft) long, it weighed about 16 kg (30 lbs), comparable to a large turkey.

Albertadromeus lived in what is now southern Alberta in the Late Cretaceous, about 77 million years ago. Albertadromeus syntarsus means “Alberta runner with fused foot bones”. Unlike its much larger ornithopod cousins, the duckbilled dinosaurs, its two fused lower leg bones would have made it a fast, agile two-legged runner. This animal is the smallest known plant-eating dinosaur in its ecosystem, and researchers hypothesize that it used its speed to avoid predation by the many species of meat-eating dinosaurs that lived at the same time. (more…)

Placental Mammal Diversity Blossomed After Age of Dinosaurs

By Guest PostFebruary 9, 2013Nature, Scienceafrica today, afrotheria, age of dinosaurs, american museum, americas, amnh, andrea cirranello, anthropologist, boundary, branching history, brazil, cloud based, common ancestor, cretaceous age mammal, cretaceous paleogene extinction, cretaceous terrestrial revolution, cyberinfrastructure, diversification, dna sequence data, earth, elephants to aardvarks, encoded by dna, evolutionary history, evolutionary trees, extinct biotic groups, federal university, fernando perini, fossil species, fossils and anatomy, fragmentation of gondwana, genetic, genetic data, genomic data, genomics based model, h richard lane, insect eating animal, john wible, kpg event, late cretaceous, mammal relationships, marcelo weksler, mary silcox, massive dataset, maureen oleary, mesozoic era, michael novacek, minas gerais, molecular clock, molecules and morphology, morphobank, nancy simmons, national museum, national science foundation, natural history, non avian dinosaurs, nsf, optimization, paleontologist, phenomic data, phenomic matrix, phenomic systems, phylophenomics, physical traits, placental mammal diversity, placental mammal tree, publicly accessible database, robb brumfield, scarborough, stony brook university, time of origin, tree of life, university of toronto, well preserved fossils

Scientists build new ‘tree of life’ for placentals, visualize common ancestor

Scientists have reconstructed the common ancestor of placental mammals–an extremely diverse group including animals ranging from rodents to whales to humans–using the world’s largest dataset of both genetic and physical traits. (more…)

Using Discards, Scientists Discover Different Dinosaurs’ Stomping Grounds

By Guest PostOctober 16, 2010Scienceceratopsians, dinosaur, duck-billed dinosaurs, fossils, hadrosaurs, herbivores, late cretaceous, montana, nicholas longrich, North America, ornithopod, period, thescelosaurus, triceratops, tyler lyson, tyrannosaurs rex, western canada, yale university, yyoming

By examining the type of rock in which dinosaur fossils were embedded, an often unappreciated part of the remains,

Certain dinosaur species liked to live in different habitats, separated by only a few miles. Image credit: Nicholas Longrich

scientists have determined that different species of North American dinosaurs from the Late Cretaceous period 65 million years ago occupied different environments separated by just a few miles.

Hadrosaurs or duck-billed dinosaurs, along with the small ornithopod Thescelosaurus, preferred to live along the edge of rivers, according to the research. Ceratopsians, on the other hand, which include the well-known Triceratops, preferred to be several miles inland.

The findings, which appear in the online edition of the Proceedings of the Royal Society B, give scientists a more complete picture of the distribution of different species and help explain how several large herbivores managed to coexist. (more…)

“Stocky Dragon” Dinosaur Terrorized Late Cretaceous Europe

By Guest PostSeptember 14, 2010Sciencebalaur bondoc, Europe, fused bones, late cretaceous, paleontologist, theropod, velociraptor

Paleontologists have discovered that a close relative of Velociraptor hunted the dwarfed inhabitants of Late Cretaceous Europe, an island landscape largely isolated from nearby continents.

(more…)

Dinosaur-chewing mammals leave behind oldest known tooth marks

By Guest PostJune 24, 2010Scienceadrosaurid, alberta, aquatic reptile, canada, ceratopsid, champsosaurus, cleveland museum of natural history, deer, dinosaur, dinosaur-chewing mammals, Epoch, femur bone, journal paleontology, late cretaceous, mammalian tooth marks, marsupial, michael j. ryan, multituberculates, nicholas longrich, ornithischian, paleontologists, royal tyrrell museum of palaeontology, university of alberta laboratory for vertebrate palaeon, yale university

New Haven, Conn. — Paleontologists have discovered the oldest mammalian tooth marks yet on the bones of ancient animals, including several large dinosaurs. They report their findings in a paper published online June 16 in the journal Paleontology.