ANN ARBOR — Like salmon in reverse, long-snouted Bandringa sharks migrated downstream from freshwater swamps to a tropical coastline to spawn 310 million years ago, leaving behind fossil evidence of one of the earliest known shark nurseries.
That’s the surprising conclusion of University of Michigan paleontologist Lauren Sallan and a University of Chicago colleague, who reanalyzed all known specimens of Bandringa, a bottom-feeding predator that lived in an ancient river delta system that spanned what is today the Upper Midwest. (more…)
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…)