What is a Corythosaurus?
Corythosaurus was a dinosaur from the hadrosaur family that lived in what is now North America. It is estimated that it remained where cypresses, ferns and magnolias grew. Its movement was that of a quadruped, but it could also stand on its two hind legs to reach higher food sources.
The first specimen was found by Barnum Brown in 1912 in Canada, near the Red Deer River, in the state of Alberta. Something that made this discovery stand out from the others is that he preserved a large part of the skin as a footprint.
This specimen was characterized by having a beak without teeth. The back of the jaws boasted a set of hundreds of small nested teeth that sharpened and grew back when they fell out.
The characteristic bony crest is similar to a helmet, which gave rise to its name. The breathing tubes that ran from the nostrils over the throat area to the crest would be an indication that it was possibly capable of producing loud sounds. Its crest was also important in mating rituals.
© Drawing by John Conway
– Creative Commons
Finding of the Corythosaurus
The first specimen was found in 1911 by Barnum Brown in the Red Deer River, in Alberta, Canada. It was an almost complete skeleton of which many skin impressions had also survived.
The lower left part was preserved in carbonaceous clay. The skeleton was articulated, and only the last two parts of the tail and the front limbs were missing. He had his shoulder blades and caraocides in position, except for the phalanges, part of the humeri, rays and ulnae.
Its remaining forelimbs were worn or eroded. The shape of its body could be established by the impressions of the integument, which covered a large part of the skeleton.
Brown and Peter Kaisen found another specimen in 1914. They can be seen in the American Museum of Natural History, in the same pose in which he died.
Barnum Brown named the species in 1914 Corythosaurus casuarius to the specimen found in 1912. He published a detailed description in 1916.
Unfortunately two remarkably preserved specimens were lost in 1916 in the sinking of the SS Mount Temple during the First World War. They were transported to England and were to be given to Arthur Smith Woodward, who was a paleontologist at the British Museum of Natural History in Great Britain.
The following species of Corythosaurus (C.) have been found:
bicristatus Parks 1935. brevicristaturs Parks 1935. cassowaries 1911. excavatus Gilmore 1923. frontalis Parks 1935 intermedius Parks 1923.
An important study on Corythosaurus was conducted in 1975 by Peter Dodson, who compared skulls and crests of different sizes and shapes. He suggested they could be related to the sex and age of each individual.
Only the characteristics of the holotype Corythosaurus casuarius are known with certainty. Some specialists have also accepted C. intermedius. That would be the specimen to which a skull found by Levi Sternberg in 1920 corresponds. It was later named in 1923 by Williams Parks in 1923. Its name is due to an intermediate position.
It would have lived shortly after the casuarius, and they are not the same species. That is why they were separated from the category in 2009.
What does Corythosaurus mean?
The name Corythosaurus originated in Greek Korythos what does it mean corinthian helmet and refers to its particular crest. Saurus On the other hand, it refers to lizard. and the epithet casuarius It was chosen for its resemblance to the bird we know today with a similar crest.
Therefore his full name translates as cassowary-like reptile that has a Corinthian crest for a helmet.
The Hadrosauroidea family
The Corythosaurus belongs to the Hadrosauroidea family, whose name means robust or corpulent lizards. They were herbivores and had a wide, flat, spoon-shaped snout. They generally did not have teeth and resembled that of a duck. Hence, reference is made to their similarity.
Their mouths were well adapted to grazing on leaves. They had a unique hinge between their upper jaw and the rest of their skull. When chewing the upper molars protruded laterally and the lower jaw worked against the upper teeth.
They belong to the Ornithischia, they moved in large herds and spread throughout the world. They are divided into the Lambeosaurinae, which had cranial ridges or tubes on the top of the head, and the Saurolophinae, which did not have crests on the skull.
It also includes ornithopods such as Edmontosaurus and Parasaruolophus, which were hebivores that lived in Asia, North America and Europe in the Cretaceous.
Hadrosaurs are descendants of the Jurassic and Cretaceous iguanodontids whose body shape was very similar.
Characteristics of Corythosaurus
Fortunately, specialists have had the opportunity to study several fossil remains of Corythosaurus, which have good support in the fossil record. As a result, they have been able to study the species. Learn more below.
Classification
Corythosaurus is a hadrosaurid, which is also found in the subfamily Lambeosaurinae. It is closely related to Hypacrosaurus and Olorotitanm. They all shared skulls and crests with a similar structure.
Specialists have also established that of all these specimens Olorotitan is the closest, although it apparently would not have most of the cranial features that distinguish lambeosaurids.
When and where did he live
Corythosaurus is known to have lived between 77.5 and 75 million years ago.. It existed over a period of about 2 million years, in the initial phase of the Cretaceous. It would have arisen during a radiation among the dinosaurs, possibly favored by large continental areas, warm climates and shallow waters.
It lived in the Oldman Formation and the Dinosaur Park Formation Area of Canada, southern Alberta. Something particular is that they had a limited area, something that seemed to be common in large herbivorous dinosaurs such as hadrosaurs. This was somewhat curious considering its relatively high mobility and large size.
Feeding
Corythosaurus was herbivorous, something consistent with its status as an ornithopod. It had a flat and delicate beak, with which it possibly fed on soft vegetation. It has been suggested that it possibly ingested selective forage, consisting only of very juicy fruit and very tender leaves.
The fossil remains in many cases preserved their thoracic cavity with remains of their last food. Conifers, fruits, seeds and twigs were identified.
Pleurokinesis: how hadrosaurids chewed
An interesting study carried out in 2009 by paleontologist Mark Purnell revealed how hadrosaurs ate. It was carried out by analyzing imperceptible scratches in the dental structure of an Edmontosaurus.
As a result, it was determined that this type of dinosaur had a unique hinge that was located between the upper jaw and the rest of its skull. Because of this, he developed a form of chewing called Pleurokinesis.
This implies that the upper jaw encloses the lower jaw. That is, it is pushed to the side and outwards when chewing. Also the lower jaw is pushed against the upper teeth.
This creates a shearing effect in which the teeth grind together precisely. The teeth of the jaws slide toward the outside of the mouth through a hinge. This is located between the joints of the premaxillary, maxillary, lacrimal and prefrontal bones.
Characteristics
Barnum Brown in 1914 noted numerous characteristics that differentiated it from the other hadrosaurs known in Alberta. Some of these have a relatively small skull compared to other similar specimens. Its crest included nostrils, forehead and entire cheeks.
It also had a narrow beak with an extension to its nostrils and a small nostril. In 1916, Brown added more particular characteristics of this specimen that would undoubtedly differentiate it from its close cousins.
These consisted of 19 dorsal vertebrae and more than 61 caudal vertebrae.. Added to this is the fact that it had spines of medium height, tail spines of high height, along with a blade of medium width and a radius that was slightly longer than that of its humerus.
Their metacarpals were relatively short, and the anterior pelvis had no curvature. The pubic bone had a front blade of short length that expanded to the ends. Its abdomen had rows of large conical scales that were located longitudinally and were separated by large polygonal tubercles.
© Daderot
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Scales
The study of the fossil remains of Corythosaurus revealed that its tail was covered with scales in a different way. In fact it had two types. On the one hand, it had some that were polygonal tubes with small protuberances. These varied in size throughout his body.
On the other hand, on the back of the shins it had conical scales, which were possibly on the lower belly. In short, its scales formed a shield and were arranged in contiguous rows.
This dinosaur is one of the few that had traces of its skin, especially the one on the hind legs and feet.
The presence of these scales has led researchers to think that it lived in water most of the time. Although this has not been proven for certain.
Lifestyle
As is often the case with herbivorous species, it is to be expected that Corythosaurus lived in large or small herds. Although it is not certain whether this also intervened in their nesting. The tendency among hadrosaurids was to live in groups to protect themselves from predation. It is a tactic that even today other animals apply in natural life.
Life expectancy
It has not been possible to determine its lifespan from the fossil evidence of Corythosaurus. Added to this is the fact that paleontologists have not yet been able to agree on how long dinosaurs existed.
Reproduction
As was the case with all dinosaurs, Corythosaurus was oviparous. They laid eggs although it is not yet known if they established colonies or what their courtship ritual was like.
Bones
Although the fossil support for this dinosaur is quite complete, the best thing it has revealed is that it had a bony crest as a skull. But it is difficult to know how many bones he had in total. Such an estimate is difficult because his skeleton has not been fully recovered.
The passage of time exposes fossil remains to crushing and reorganization processes that complicate the possibility of making an estimate of the quantity of their bones.
Communication
It had a bony crest on the top of the skull, whose function was not exactly to strike. It is also believed that he had the ability…