| Ornithomimidae |
 The Ornithomimosauria or Ornithomimidae ( "Imitations of bird" in Latin) commonly called "ostrich dinosaurs" because of their morphological characteristics, were dinosaurs theropods of medium size, long neck, beak edentulous (except for species the most primitive) with big eyes and long legs built for the race. They lived on in Laurasian Cretaceous Lower Cretaceous higher, until the Cretaceous extinction. It is possible that they appeared to go from the Jurassic, although it is not yet confirmed. Description Head Gallimimus bullatus This group is characterized by their small size (no more than 3 meters high), with a long neck, a head with big eyes, the brain relatively large contribution by the rest of the body, long arms with three-fingered hands with long, curved claws, the long legs made for a high speed, feet trydactiles (probably with a pin smallest behind) and an equally long tail which was used as a stabilizer in the run. Among the most primitive species, the beak is slender and has two jaws on a line of hundreds of small jagged teeth and a bony crest on top of the head, similar to that of some pterosaurs (pelecanimimus may be of also easily confused with a ptérosaure because of the unusual nature of his skull), whose exact function is unknown. It is assumed that ornithomimés could have a bag shaped to hold the food, which was proven in pelecanimimus. Behavior Hand Struthiomimus It is assumed that they were gregarious and they lived in groups of several dozen people, at least for the most advanced specimens. They were intelligent animals, the brain cavity of the skull was their big contribution to their bodies in addition, their vision was excellent, thanks to their large eyes associated with their large brain. It is unclear how their nests were and how they will raise their children, but it is likely that, like the vast majority of bipedal dinosaurs gregarious and ratites, they made collective nests and raise their young in groups to a certain age . Except perhaps for the Deinocheirus, their defenses were limited and in the face of larger predators, the flight would be the most effective solution, which is confirmed by their morphology based on the sprint. Food This model of Ornithomimus shows a specimen eating eggs, one of his theory on food. Most scientists agree that ornithomimés were omnivores to dominant herbivore; were found gastrolithes to the location of its stomach. Moreover, according to the frequency of fossil bones found species of this taxon, they were the most numerous smaller dinosaurs in North America in the Late Cretaceous, which is consistent with the fact that they are herbivores, or at least in a majority, since in a given ecosystem species herbivores outnumber carnivorous species. Henry Fairfield Osborn suggested that the strange arm, long and end with a hand in three longand curved claws, could have been used to seize the high branches of trees and then dissect their leaves, which later conducted some studies on their hands this particular taxon strongly supports. In 2001, scientific studies conducted on the skull ornithomimés advanced showed that these species had, in their beaks, vertical slats similar to those found in ducks modern and suggested they would be able to filter, leaving their beaks flush with water for capturing microorganisms for food. However, other scientists argued that such structures could skull is found in many varieties of animals not filter with a spout, like turtles. They had to eat leaves, young inches, fruits and seeds, and may be small animals such as lizards, small mammals and amphibians. It was also suggested that they could feed on the eggs of other dinosaurs, although there is no evidence at present. The long beak and teeth of the most primitive species suggests a carnivore, it is not impossible that they were scavengers or eating (This is quite likely in the case of pelecanimimus, the remains were found not aillant far from what was a lake at the time of the death of the animal, and, of course, because of the presence of a large crop) Plumage Reconstitution with a feather Struthiomimus The ornithomimés are a group of close maniraptores, and we suppose they could have proto-feathers and maybe some feathers more advanced, particularly for behavioral (Socialization, group cohesion, courtship). At present, no permit has fossil discovered to confirm this theory, because of the nature of the rocks containing the bones. However, their birds (including the neighboring family, the Alvarezsauridae) strongly suggest this feature. If they had proto feathers or down, they are likely to have covered the upper body from head to tail, and the upper sidewall. It is very unlikely to have possessed ornithomimés in the legs and stomach as this could hamper their movement and speed during the race. Similarly, too many feathers on the body would have a similar effect, particularly on his stomach, legs and arms. against by the presence of long feathers on the head and quills on the tail is not unlikely, the latter could be useful in a sprint. Any crest of feathers on the head would also have had a social function.
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