In Depth
Although only described from very incomplete remains, the relatively good state of preservation of them has allowed for the description of a new genus, Albertadromeus. Albertadromeus is believed to have been a small cursorial (ground dwelling) ornithopod that roamed around on just its two rear legs. The preserved limb elements known show that the distal ends of the tibia and fibula (the lower leg bones) of Albertadromeus were fused. This is the inspiration for the type species name ‘syntarsus’. At the time of its description Albertadromeus has been considered to be closely related to the dinosaurs Orodromeus and Zephyrosaurus.
The description Albertadromeus has also been used to support the increasingly popular idea that small dinosaurs like Albertadromeus were far more common in the late Cretaceous that previously thought. The simple reasoning is that smaller animals have smaller and more delicate bones which are less likely to survive the ravages of environmental conditions and the mouths of hungry carnivores. Also in 2013 another small dinosaur discovery, the early pachycephalosaur Acrotholus, was used to support this theory.
The Albertadromeus holotype remains were discovered in the Oldman formation of Canada, indicating that Albertadromeus may have spent its time foraging amongst other herbivores such as the hadrosaurs Parasaurolophus and Corythosaurus, and ceratopsians such as Chasmosaurus and Albertaceratops. Danger however would come from small dromaeosaurs and troodonts such as Saurornitholestes, Troodon and Hesperonychus. Bigger threats would have been tyrannosaurs such as Daspletosaurus, and while a large adult would have likely had a very difficult time catching a small and nimble dinosaur like Albertadromeus, younger juvenile tyrannosaurs are noted for their potential speed. It may be that juvenile Daspletosaurus hunted small dinosaurs like Albertadromeus before graduating to larger hadrosaurs and ceratopsians in later adult life.
Further Reading
- New data on the diversity and abundance of small-bodied ornithopods (Dinosauria, Ornithischia) from the Belly River Group (Campanian) of Alberta, C. M. Brown, D. C. Evans, M. J. Ryan, A. P. Russel - 2013.
