por He ankylosaurus (Ankylosaurus magniventris) It was a dinosaur that inhabited the north of the American continent during the Cretaceous period of the Mesozoic Era. Its fossils were first described in 1908 by the American paleontologist Barnum Brown. This is the only species of the genus Ankylosaurus discovered so far.
The peculiar appearance of this dinosaur has drawn the attention of specialists. Its protective shell and its tail were its characteristic elements, which guaranteed it protection against possible predators or contenders it might encounter.
Ankylosaur Characteristics
The ankylosaur was considered a multicellular eukaryotic organism, that is, it was made up of a wide variety of cells, each specialized in different functions. Likewise, the cells had a nucleus within which the DNA was found, forming the chromosomes.
From the point of view of embryonic development, specialists consider that this animal could be triblastic and therefore had three embryonic layers: ectoderm, mesoderm and endoderm. From them the organs that made up the adult individual were formed.
This was an animal with bilateral symmetry, that is, its body was made up of two exactly the same halves that were joined in the longitudinal plane.
Likewise, it could be considered a peaceful dinosaur, although when it felt threatened it could be really ferocious, especially when it used its long tail with its caudal club.
This dinosaur was considered an animal with solitary habits that only joined individuals of the same species when it was time to mate. It reproduced sexually, with internal fertilization, and it is believed that they were oviparous.
taxonomy
The taxonomic classification of the Ankylosaurus is as follows:
Animalia Kingdom
Edge: Chordata
Subphylum: Vertebrata
Superorder: Dinosauria
Order: Ornithischia
Suborder: Thyreophora
Infraorder: Ankylosauria
Family: Ankylosauridae
Genus: Ankylosaurus
Species: Ankylosaurus magniventris
Morphology
The ankylosaurus is one of the dinosaurs that attracts the most attention due to its morphology, especially due to the amount of bony plates and spines that covered its body on the dorsal surface. The shape of its tail was also quite peculiar, since at the terminal end it presented a widening known as a club or mallet.
This dinosaur was large. According to data collected from fossils, it could weigh up to 4,500 kilograms, its measurements were between 6 and 9 meters long and it could reach a height of almost 2 meters.
Head
The head was small compared to the rest of the body. This could measure up to 64 cm in length. The eyes, which were housed in orbital sockets whose size was rather oval, were not oriented to the sides, but almost to the front.
The opening of the buccal cavity (mouth) was surrounded by a kind of beak. Its teeth were shaped like a jagged blade, suitable for cutting vegetation.
Above the eyes they presented a kind of pyramidal horns, which pointed backwards. It is believed that these were osteoderms fused with the skull.
Body
The ankylosaur’s body was quite robust, broad and compact. It had four limbs, of which the posterior ones were the longest.
The most prominent feature of his body was the armor that protected him, which was quite resistant. This was made up of a large number of plates or osteoderms that were embedded directly into the skin of the animal.
It is believed, from the analysis of some fossils, that these plates were also on the neck, forming a kind of protective cervical rings.
Line
The complete structure of the tail remains unknown, since no fossils have been found in which it is complete. However, the element that until now is considered the most important of this is known: the so-called baton.
At the end of the tail there was a kind of expansion that served the ankylosaurus as protection against possible predators or for fights between them during mating rituals.
This club or mallet was made up of several fused vertebrae, reinforced by tendons that were ossified.
Thanks to its structure, the tail was one of the most important elements for the survival of the animal, since it allowed it to protect itself and get away with any attack. Specialists affirm that even a blow with the tail could break the bones of his opponent.
Habitat and distribution
The ankylosaurus was a dinosaur that lived mainly in the northern part of the planet, specifically in the American continent in the area that today belongs to North America.
Some specialists in the subject state that the ankylosaur inhabited an island that was located on the west coast of the North American continent, known by the name of Laramidia.
The characteristics of the habitat in which the ankylosaur developed were compatible with forests and riverbanks. The forests covered large tracts of land and were very humid.
According to the fossils of the plants that inhabited these spaces, specialists have managed to reach the conclusion that the type of plants that abounded there were among the most evolved, that is, with flowers and fruit that could be fleshy.
It has been established that the ankylosaurus had a predilection for spaces near rivers, since this way they had access to the two most important resources: water and food.
As regards the climate of this habitat, it is confidently stated that it was tropical or subtropical, in which humidity and temperature were high.
Until now, it is totally denied that the ankylosaur lived in areas close to the maritime coasts. Therefore, it has been established that it was located in the inner part of the continent or on the island of Laramidia, mentioned above.
Feeding
The ankylosaur was a herbivorous animal; that is, it fed purely on plants. Due to its small stature, it is believed that it fed only on the plants within its reach, so it grazed low.
Likewise, based on the characteristics of its skull, scientists agree that the animal could only move its jaws up and down, so it was possible that it only fed on soft vegetation. Despite this, there are others who affirm that the jaw did have more mobility, so it could also feed on slightly harder plants.
With regard to its digestive process, it can be affirmed that the ankylosaur practically did not chew its food, but rather swallowed it whole. It is possible to reach this conclusion after studying the characteristics of your teeth. Its teeth were very small, ideal for cutting leaves, but not for chewing and crushing them.
Digestion
Digestion occurred in the intestine. According to what was exposed by various specialists, in the intestine of the animal it was possible that there were several chambers in which the food was fermented in order to be assimilated by it.
Here perhaps what is observed in many current herbivorous animals could occur: the existence of certain bacteria that contribute to the degradation of substances such as cellulose so that the animal can assimilate and take advantage of certain nutrients.
Finally, the animal released into the environment the waste product of its digestion, consisting of substances not used by the animal’s body.
Reproduction
Regarding their reproduction, it can be said that, like all members of the Chordata phylum, they reproduced sexually. This means that a female and a male had to mate, providing the gametes so that they would fuse and give rise to the formation of a new being.
courtship ritual
According to experts on the subject, it is believed that the ankylosaur was a solitary animal. However, when it was time to mate, several would gather. Apparently this could happen once a year.
However, among the ankylosaurs there was a courtship ritual, in which the males fought with each other, making use of the clubs of their tails. Finally there were only two left and eventually one of them gave up the fight, so the other was the winner. This was the one who earned the right to mate with the most females.
This type of behavior is not alien to the animal kingdom, since it is also observed in some other species of animals that persist today.
fertilization and development
It is believed that fertilization was internal, that is, it occurred inside the female’s body. For this, the male had to have a copulatory organ to help him.
However, it is important to clarify that these are conjectures resulting from the suppositions of specialists, since the structures involved in reproduction were soft parts of the body and these, in general, do not leave fossils.
The specialists suppose that the immense shell of the ankylosaur could constitute an element that interfered negatively with the reproductive process. To shed some light on this, they have compared the mating process of the ankylosaur to that of turtles.
According to this, male ankylosaurs would have a very long copulatory organ (penis), through which they could connect with the female’s cloaca and deposit sperm there.
Once this was done, the fusion of gametes occurred and the new being originated.
Now, it is believed that the ankylosaur was an oviparous animal; that is, the new individuals developed in eggs outside the mother’s body. The incubation and development time remain unknown, as well as whether they had direct or indirect development.
Extinction
According to fossil records and data collected by specialists in the area, the ankylosaur lived until the Cretaceous-Paleogene mass extinction. It is believed that it succumbed in the same mass extinction process in which more than 98% of all dinosaur species that inhabited the planet perished more than 65 million years ago.
In this sense, the causes of this mass extinction event have not been established with complete certainty. However, the hypothesis that has gained the most strength among the scientific community is that of the meteorite.
the meteorite
Scientists believe that approximately 65-66 million years ago, a large meteorite impacted the planet, specifically on the site that is now occupied by the Yucatan peninsula. Here they discovered a large crater that would show that this theory would be true.
The fall of this meteorite was a global catastrophe, generating a drastic change in the planet’s environmental conditions, which significantly affected the lives of the vast majority of animal and plant species that inhabited the planet.
Volcanic activity
Likewise, there are also records that there was intense volcanic activity in the area that…