What is a Micropachycephalosaurus?
Micropachycephalosaurus was a dinosaur that lived in the Cretaceous period between 83 and 70 million years ago.. It is currently considered to belong to the ceratopsid ornithischians.
It was a small animal, hence the term is included in its name. micro. It is in fact one of the smallest that has been found in the history of paleontology.
His remains were found in what is now China, where he had enough vegetation to sustain his existence.
He was less than half a meter tall and his body volume did not exceed 20 kilos. She lived in the Shandong area, in the Asian country. It is possible that its skin had a texture similar to the plants of that time, with several stripes or lines that allowed it to camouflage itself and thus defend itself from predators.
He was terrestrial, and did not worry about climbing trees or reaching vegetables that were not at his height. He consumed plants that grew at ground level, something that prevented him from competing with other animals, which fed on those that were high.
Because of this, it is estimated that his diet was abundant, which allowed him to maintain a high level of energy during the day. Its length could range between 50 cm and 1 meter. And its volume was a maximum of 20 kilos.
Its skull was not as solid as some paleontologists initially believed. It was found that it could be fractured by average blows. Therefore they did not use it to defend themselves. Nor to confront each other during the mating season.
In these circumstances it is possible that they only delivered a few thrusts to confront their opponents and thus dissuade them and make them retreat from the fight.
Finding of the Micropachycephalosaurus
The first description of Micropachycephalosaurus was in 1978. The holotype specimen was found southwest of Laiyang, in what is the state of Shandong. Curiously, it was near the Hongtuyan train station.
Dong Zhiming was the one who made the discovery and made the description. He initially classified it as part of the Wangshi Formation.
The material was interpreted as a minor member of the Pachycephalosauria. It included parts of the skull, of which it had the left square, two rows of teeth and part of the lower skull.
To these are added three posterior vertebrae, two sacral vertebrae, parts of the seven caudal vertebrae and part of the left hind leg, which included a piece of the left pelvic leg. Added to this is also a well-preserved and the tip of a pimple.
Much of the material disintegrated during the excavation process. What remained were some pieces with only footprints left in the rock that surrounded the fossils..
Subsequent studies found their own characteristics that differentiated them from Pachycephalosaurus. One in particular from 2009, carried out by Richard J. Butler, indicated the presence of unique and prominent longitudinal grooves on the underside of the ventral centers, in the posterior area of the back, which was something that distinguished it.
Their conclusion was that it was the fossil of an individual located somewhere in the Cerapoda. He also indicated the slightly higher possibility that he was a member of the Ceraptopsia.
Later in 2011, Richard J. Butler himself, together with a group of collaborators, carried out a cladistic study determining that Micropachycephalosaurus was a basal member of the Ceratopsia.
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The Marginocephalia family
The Micropachycephalosaurus is part of the Marginocephalia family, whose name means marginal heads. It is also part of the small and medium-sized Ornithischia suborder.
Within this family the Ceratopsia and the Pachycephalosauria are grouped. All the animals in this group had a diet exclusively based on vegetables, so they were herbivores. Their form of movement could be bipedal or quadrupedal.
Its most notable feature was a thickened, shield-shaped bony cap that reached to the nape of the neck at the end of the skull. Their edges also had bony spikes or small horns.
Its first representatives lived in the Upper Jurassic, and during practically the entire Cretaceous, a time in which many species prospered.. Its diversity ranges from small specimens to individuals carrying several tons.
They were distinguished by particularities in the pelvis, pubis and ischium. In the same way, they had decorations on the skull and a nuchal shield that distinguished a Marginocephalia from others.
They also had simple conical teeth that were surrounded by a keratin sheath. These pieces were organized in batteries, which were quickly replaced and which were suitable for the consumption of plant matter.
What does Micropachycephalosaurus mean?
The name Micropachycephalosaurus is based on the term assigned to Pachycephalosaurus. This came from Greek pachis which means thick, kephale which translates as head and saurus What does it mean lizard either reptile. Hence it is translated as hard headed lizard.
Because in this case we are dealing with a similar specimen, but smaller in size, we add micro. So the meaning of Micropachycephalosaurus It’s of small hard headed reptile.
The epithet hongtuyanensisdesignates the area where his remains were found, which is in the vicinity of the Hongtuyan train station.
Characteristics of Micropachycephalosaurus
This dinosaur has been the target of various studies, which have revealed a little more about this tiny species, which lived in prehistory. To learn more, continue reading below.
Classification
In his preliminary classification, paleontologist Dong Zhiming placed it as a member of the Pachycephalosauria. This was a group of bipedal herbivores with a large, iron dome on the top of their skulls, which was also called a dome head.
However, in 2006 this was questioned. Two years later Zhao and Butler did not find any particulars that related it to Pachycephalosaurus. The only thing it seemed to have in common was the domed skull, which was absent in the samples that the specialists had, so they did not ask to support or refute the initial designation.
Because of this Zhao and Butler concluded that he was an undetermined member of the Ceratopsia. In 2011 it was announced that he was a basic member of this group.
Feeding
The diet of this dinosaur was herbivorous. It fed on plant matter that included seeds, plants, and fruits that it consumed most of the time. It had a row of small, sharp teeth at the back of its jaw, with which it chewed what it ate. Although it was biped, it sometimes moved on its four legs to find food.
Habitat
Its remains were in the Jiangjunding Formation of the Wanshi group. This stands out for having reddish sandstones, siltstones and conglomerates. This formation was deposited in an environment with characteristics between fluvial and lacustrine.
So the weather was hot and humid most of the time. It began to dry out after this time. In this area also coexisted the Ankylosaurus pinacosaurus grangeri and the Hadrosaurus sinensis. Added to this were intermediate sauropods and celurosaurus and some chelonians.
Then the vegetation was abundant and stood out for grasslands that provided a varied diet.
How he lived
The tendency among dinosaurs was to be gregarious or live in herds. Taking into account the fossil evidence in which Micropachycephalosaurus was found, everything seems to indicate that it was an animal that lived alone.
Reproduction
It was an oviparous animal, meaning it reproduced by laying eggs. A female was capable of laying up to 21 eggs in a clutch. The juvenile specimens hatched after a certain incubation time. It is not clear if they cared for the babies or if they had to learn to survive alone.
Communication
It is possible to infer that their form of communication was similar to that of other dinosaurs. That is to say, they made use of their bodies and vocalizations. These animals used different sounds with their mouths open and also with their mouths closed.
In the same way they made use of colors in the domes of their skulls, chest armor and ornaments that they used to show off during the mating season, in order to impress potential mates. In the same way they would use them to scare rival dinosaurs.
Speed
Due to its size and structure, Micropachycephalosaurus could run very fast. Because they were small, running and hiding was the only thing they could do to avoid being eaten by predators.
The fact that they had a light and reduced body volume was vital so that they could move with agility. There are no studies that have determined its speed precisely. Footprints under the layers of the earth are usually used to determine this. But in this case no one has been found to help in the task.
Behavior
Given their characteristics, it is possible to deduce that they were not very aggressive animals, since due to their size they were more likely to end up as the prey of another dinosaur. Speed was his best defensive strategy.
When did Micropachycephalosaurus become extinct?
Micropachycephalosaurus existed between 83 and 70 million years ago, during the Cretaceous period.. Some specialists place its end with the mass extinction that began the Paleogene. However, this is not known exactly. Most actually believe that they perished before that, due to factors that cannot be known.