is thought to have been a herbivore. It had a broad muzzle, which could indicate that it was a non-selective feeder, perhaps similar to a hippopotamus. This would provide niche separation from contemporaneous nodosaurids with narrower muzzles. Ankylosaurians have historically been thought of as feeding using simple up-and-down movements of the jaws. Georg Haas (1969) examined the evidence for the jaw muscles of two skulls (AMNH 5337 and 5405) and concluded that despite the large size of the skulls the associated musculature was relatively weak. He also thought jaw movement was largely orthogonal, in the vertical plane only. Haas extrapolated from this that dinosaurs like Euoplocephalus likely ate relatively soft non-abrasive vegetation. However, later research indicated that forward and sideways jaw movement was possible, the skull being able to withstand considerable forces. Euoplocephalus appears to have been able to make more complex movements. Tooth wear and jaw articulations (within the lower jaw and at the lower jaw-quadrate joint) suggest that the lower jaws were pulled back during feeding, and also slightly pivoted inward. This action would have sheared food. A study conducted in 2014 found that the ankylosaurs were capable of eating of tough fibrous plant material, though not to the same degree as their nodosaur relatives or the ceratopsians and hadrosaurs. See also Timeline of ankylosaur research References External links Fossils of Canada Ankylosaurids Late Cretaceous dinosaurs of North America Fossil taxa described in 1910 Taxa named by Lawrence Lambe Dinosaur Park fauna Paleontology in Alberta Campanian genus first appearances Campanian genus extinctions Ornithischian genera