Struthiomimus — Struthiomimus was a long-legged, ostrich-like dinosaur of the family Ornithomimidae, which lived in the area that is now Alberta, Canada, during the late Cretaceous Period, approximately 75 million years ago. Its generic name is derived from the Greek strouthion meaning ’ostrich’ and mimos meaning ’mimic’ or ’imitator’. The specific name altus is from Latin, meaning ’lofty’ or ’noble’.
The bipedal Struthiomimus stood about 3.7 meters long and 1.4 meters (4’6”) tall at the hips and weighed around 150 kg (330 lb). Struthiomimus is one of the more common small dinosaurs in the Dinosaur Provincial Park; its abundance suggests that it was a herbivore or omnivore rather than a carnivore.
Its neck was slender and ended in a small, toothless, beaked skull, with relatively large eyes. The arms of Struthiomimus were long and comparatively strong; the fore limbs were more powerful and the claws were more strongly hooked than in Ornithomimus. There are similarities to modern-day sloths. It also had the typical characteristics of most ornithomimids: a long, stiff tail and a toothless beak.
It is possible that Struthiomimus had feathers, like many of its relatives.
There has been much discussion about the feeding habits of Struthiomimus. Because of its straight-edged beak, Struthiomimus may have been an omnivore. Some theories suggest that it may have been a shore-dweller and may have been a filter feeder.
Some paleontologists noted that it was more likely to be a carnivore because it is classified within the otherwise carnivorous theropod group. This theory has never been discounted, but Osborn, who described and named the dinosaur, proposed that it probably ate buds and shoots from trees, shrubs and other plants, using its forelimbs to grasp branches and its long neck to enable it accurately to select particular items. This herbivorous diet is further supported by the unusual structure of its hands. The second and third fingers were of equal length, could not function independently, and were probably bound together by skin as a single unit. This indicates that the hand was used as a “hook”, for bringing branches or fern fronds within reach.