II➤ Plateosaurus – Resumenea

NamePlateosaurus engelhardti SizeLarge EraMesozoic PeriodTriassic FoodHerbivore HabitatEurope NatureTerrestrial

What is a Plateosaurus?

The Plateosaurus was one of the first large dinosaurs. It was a sauropodomorph that lived 210 million years ago during the Triassic. His remains were found in what is now France, Switzerland and Germany.

Johan Friedrich Engelhardt found the first specimen in 1834. Paleontology itself did not exist then, because this word began to be used only a few years later. What there was was an interest among biology specialists in discovering what those enormous skeletons were that were beginning to appear in the world.

Type species were then discovered and assigned invalid names or minor synonyms. Over time this dinosaur became one of the best understood. The discovery of about 100 practically complete skeletons profoundly benefited the development of paleontology.

It is estimated that it closely resembled carnivorous theropods such as Tyrannosaurus. But it was actually a giant herbivore, so it is unlikely that it was aggressive. It was tall, something that allowed it to eat plants and fruits in high places that other animals could not access.

It is known that it walked on two legs and used its short forelimbs to search for food. Possibly they also served to defend himself.

Plateosaurus discovery

The first discovery of this species was in 1834. At that time the German doctor Johan Friedrich Engelthardt found leg bones and some vertebrae in Heroldsberg in Nuremberg, Germany.

Paleontologist Herman von Meyer designated this specimen as a holotype and named it Plateosaurus just three years later. Later between 1910 and 1930 excavations were carried out in Saxon Anhalt in a clay pit.

There they found about 50 skeletons that included the species Halticosaurus, Liliensternus and Plateosaurus. Some of these were assigned to Plateosaurus longiceps which was described in 1914 by Otto Jaekel.

In 1997 there was a discovery on an oil platform in Snorre, in the North Sea. A sandstone drilling found a fossil cylinder more than 2,000 meters below the seabed. Inside it had a fossil that seemed to be composed of plant matter.

Jørn Harald Hurum, who was a paleontologist at the University of Oslo, studied them in 2003. Research together with specialists from the University of Bonn determined that it had fibrous bone tissue and that it belonged to a Plateosaurus. This was the first dinosaur found in Norway. It was also the deepest in the entire world.

The most recent discovery was in 2007 by an amateur paleontologist. He found a pit with more than 300 bones that included parts of Plateosaurus. A paleontologist from the University of Bonn, Martin Sander, assured that this area had an extension of 1.5 kilometers.

It is currently considered the largest fossil site in Europe, with one dinosaur per 100 square meters.

What does Plateosaurus mean?

The name Plateosaurus comes from the Greek platys what does it mean flat either broad. It is also related to set either flat surface. Added to this is saurus What does it mean lizard. Therefore the entire name translates as flat or wide lizard. It refers to the flat bones of the animal. The epithet engelhardti It was added in tribute to the discoverer of the first specimen.

The Plateosauridae family

The Plateosauridae family, to which Plateosaurus belongs, is made up of sauropodomorph plateosaurs who lived during the last phase of the Triassic in Asia, Europe and Africa.

While classifications have varied over the years, this family is currently considered to be restricted to Plateosaurus.

In 2003 it joined Sellosaurus among the Plateosaurus under the name Plateosaurus gracilis.

It was Othniel Charles Marsh who named the group as Platesauridae in 1895. Paul Sereno defined it in 1998 as the gathering of all the specimens that had a closer relationship with Plateosaurus engelhardti what with Massopondylus carinatus.

In 2004 Galton and Upchurch defined it as all the specimens closest to P. engelhardti that to Yunnanosaurus huangi and Massospondylus carinatus.

Again in 2007 Yates redefined them as those closer to P. engelhardti than to Diploducus longus.

Other analyzes of the clade suggest that the Prosauropoda group includes all animals most closely related to P. engelhardti what with Saltasaurus loricatus. It is a synonym of Plateosauridae because they both contain the same taxa.

Plateosauridae was discovered as a monophyletic group in the large study of the first fossil specimens carried out by Baron, Norman and Barret in 2017 and which was published in the publication Nature. This details that the group within the Plateosauria clade was brother to the so-called Massopoda.

Plateosaurus Characteristics

Plateosaurus is fortunate to have extensive representation in the fossil record. This has allowed us to study it and learn a lot about its characteristics. Get to know them below.

Classification

It is the first prosauropod to which a description was made. It gives its name to the Plateosauridae family, which is the one it belongs to. At first it was included only among the saurians.

Later, in 1845 Von Meyer created the group Pachypodes that brought together Hylaeosarus, Megalosarus, Iguanodon and to Plateosaurus.

Plateosauridae was proposed in 1895 by Othniel Charles Marsh and placed within the theropods. It was later transferred to the Prosauropoda by Huene, something that many authors of that time accepted.

For a long time the clade only contained Platesaurus, but in recent years the genera have been added. Sellosaurus and Unaysarus.

When he lived

Plateosaurus lived between 225 and 219 million years ago, in the last phase of the Triassic period. Some of his contemporaries were the Saltopus which was a theropod and the Proganochely which was a species of turtle.

Paleoecology

In certain sites, groups of individual fossils have been found that were also complete. This would be indicative that it lived in herds that traveled through the arid desert that made up Europe during that period.

This would have allowed it to find suitable places with abundant food sources. They coexisted with other prosauropods, theropods, turtles, primitive mammals, pterosaurs, sphenodontids and fish.

Another theory suggests that in reality their behavior was solitary and that they lived in high, arid areas. When their remains died, they were displaced by frequent floods that piled them up in flood channels that arose in desert basins.

Feeding

Although everything indicates that it was herbivorous, the study of the shape of the crown of its teeth revealed similarities with herbivorous or omnivorous iguanas that we know today. Therefore this opens the possibility that it was also fed meat.

Their diet consisted mostly of plants and fruits.. Her teeth were prepared for chewing and grinding vegetables. However, scientist Paul Barrett suggested that prosauropods supplemented their diet with carrion or small animals as prey.

In the same way it is considered that it could have been cathemeral. This would indicate that it would be active to feed either day or night. It would usually take shelter to avoid the hottest times of the day.

Its growth pattern was similar to that of other non-avian dinosaurs. Its rate of development and the final size of an adult specimen was variable. Some reached their largest size at 4 meters long and others at 10.

Its rapid growth could be indicative that it possessed thermoregulation, preserving its body temperature within certain limits.

Motion

For a long time, various theories abounded about the locomotion of Plateosaurus. Initially it was thought to be quadruped. Then someone proposed that he could jump like a kangaroo, something that was quickly discarded.

It was also proposed that he would have alternated between bipedal and quadrupedal walking. This idea was accepted until Bonnan and Senter’s study in 2007. They showed that Plateosaurus could not pronate its hands, which would not have allowed it to walk on all four legs.

This is how they concluded that it was bipedal and therefore walked on its hind legs.

Physical characteristics

It was a leaf-devouring animal, thin and tall. It had a skull and a long, flexible neck. His hind limbs were very strong, as were his arms. Although the latter were short and did not allow him to lean on them, so he was bipedal.

It had large claws on its hands with which it could obtain its food and even defend itself.. Its eye sockets were on opposite sides of the skull, which is indicative that it had panoramic vision that allowed it to detect potential predators.

One of its most important adaptations was bird-like lungs, whose large volume of air allowed it to look larger than it was.

Development

The study of fossils indicates that the size of these individuals could be variable. These variations could be related to their environment. In some cases they reached their maximum size at 12 years of age.

In other cases they continued to grow beyond 20 years. The size of adult individuals varies, since some were already mature at six meters in length and others were already developed at ten meters in length.

Although its bone histology is well documented, no specimens less than 5 meters long have been found, which would allow us to better understand its growth. But its high rates of development suggest that its dinosaur physiology was advanced.

Bones

Although there are about 100 specimens in the fossil record, it has not been possible to determine the total number of bones it would have had. One estimate indicates that there could have been close to 200.

Communication

Plateosaurus would have communicated through loud roars, which may have been its primary form of communication. These would be combined with bellows, or muffled noises, which they would use to attract the attention of sexual partners. To this would be added visual displays, such as lifting with the front legs, whipping with the tail or stomping.

Speed

Because it was a medium-sized biped, it is possible that its speed was around 6 km per hour. To this we must add a maximum speed of 88 km per…