We open the category of ornithopods from the historically second described terrible lizard (the first was the megalosaurus). Scientists often coined the names of dinosaurs for conspicuous features. Latin translates as "iguana tooth" due to the similarity of the teeth with the aforementioned lizard. Apparently "iguana-toothed" well adapted to the conditions of the external environment, so they managed to spread almost all over the globe!
Time and place of existence
Iguanodons existed in the early Cretaceous, about 126 to 125 million years ago. They were distributed in the territory of modern Belgium. Fragmentary remains that may belong to this genus are also found in some other European countries. 
The iguanodon was a large herbivore with a massive body reaching about 10 meters (33 feet) in length and weighing up to 3.5 tons. The arms were long (up to 75% of the length of the legs) and strong, which suggests that he spent a significant part of the time standing with all his limbs on the ground, eating food, but in case of danger, he could move quickly on powerful hind legs. The forelimbs had 5 fingers, of which the three middle fingers were the most developed, the thumb on the hand had the shape of a large conical thorn at right angles to the other fingers of the hand. The hind limbs had three large toes, the bones of the limbs were powerful, and the spine was reinforced with rigid tendons.
Published calculations suggest that the iguanodon could reach speeds in a bipedal position of up to 24 km / h. The speed when walking on four legs was probably lower. These large animals had narrow skulls with a toothless beak, probably covered in keratin. The upper jaw contains up to 29 teeth on each side, the lower jaw up to 25 teeth, the teeth in the lower jaw were wider than in the upper.
Given the deep placement of the teeth in relation to the outside of the jaws, the iguanodon had a peculiar cheek to hold food in its mouth. When the jaws were closed, the upper jaw turned outward, which led to a chewing motion. The teeth were grouped into "batteries" as they were constantly replaced and the iguanodon could feed on tough plants. Iguanodons could eat food both at ground level and at an altitude of four to five meters, according to Norman, his diet consisted of plants such as conifers and palm ferns. The iguanodon is considered to be the dominant large herbivore in its habitat.
Types and history of detection
So far, one species is generally recognized, which is accordingly a type: Iguanodon bernissartensis. A few more are under discussion due to the doubtfulness or the small amount of material.
England is not only home to creative innovation. Important paleontological discoveries were made there. The first fossilized iguanodon bones were found in Sussex by Gideon Mantell. His wife Mary was very helpful. Mantell published the description in 1825.
In 1878, an important discovery of an entire iguanodon cemetery takes place in a mine ravine near the Belgian town of Bernissart. At a depth of 322 meters. As many as 38 well-preserved skeletons, some of which are almost complete. The fossils have greatly advanced research on iguanodontids. They are now on display at the Royal Institute of Natural Sciences in Belgium. New finds appear periodically in different parts of the world.
Body structure
The body length of the ornithopod reached 10 meters. The height is up to 5 m. Iguanodon weighed up to 3 tons.
Head
The head of an iguanodon, about one meter long, ended in a beak, with the help of which the dinosaur tore off foliage and nibbled on small bushes. The iguanodon's head was shaped like the head of a modern horse. Iguanadon had no front teeth. The dinosaur chewed food with its teeth located in the depths of its beak. There were about a hundred teeth in the mouth of iguanadon, similar to teeth.modern iguana, only much larger. The food was frayed as the jaws moved along. Another notable feature of the iguanodon was the presence of cheek-like skin sacs in which food was trapped when chewed.
Limbs
Iguanodon moved on four legs, but sometimes got up on its hind legs to escape from enemies or eat vegetation growing at a height of 5-6 meters. The front legs were a quarter shorter than the hind legs, rested on three central toes. The forelegs looked unusual. The forelimbs of the iguanodon had 5 toes. The fifth finger was not quite an ordinary finger. It was in the form of a large spike about 20 cm long and was relatively mobile and most likely served as a means of defense against predatory dinosaurs, for example baryonyx or flocks yutaraptorov... The five-fingered hand was well adapted to gripping branches so that the iguanodon could more easily eat them. The hind legs were not much longer than the front ones and had three toes.
The forelimbs are fairly well developed. Moreover, the structure of the hands is somewhat human-like. The middle three toes were strong and ended in flat hoof-like claws. They were used for support when moving. The flexible fifth finger served as a thumb for humans to grab objects (for example, when the iguanodon tilted branches or gnawed at the stems). A kind of "big pinky". But the most amazing finger is the first. It lacked intermediate joints, creating a sharp spike about 20 cm long! Most likely, its main purpose is a weapon of protection against predators. Perhaps they also used the iguanodon to drive away rivals in the herd or to use them to get special food.
A rigid tail, flattened from the sides, served as a classic support for balance.
The skull, vaguely similar to that of a horse, ended in a bony beak, with which the iguanodon plucked plants. Strong teeth, indeed like an iguana, were quite suitable for thorough chewing. There were 29 on the upper and 25 on the lower jaw.
Males were larger than females, which is observed in many modern animals.
Video
We open the category of ornithopods from the historically second described terrible lizard (the first was the megalosaurus). Scientists often coined the names of dinosaurs for conspicuous features. Latin translates as "iguana tooth" due to the similarity of the teeth with the aforementioned lizard. Apparently "iguana-toothed" well adapted to the conditions of the external environment, so they managed to spread almost all over the globe!
Business card
Time and place of existence
Iguanodons existed in the early Cretaceous, about 126 to 125 million years ago. They were distributed in the territory of modern Belgium. Fragmentary remains that may belong to this genus are also found in some other European countries.Types and history of detection
So far, one species is generally recognized, which is accordingly a type: Iguanodon bernissartensis. A few more are under discussion due to the doubtfulness or the small amount of material.England is not only home to creative innovation. Important paleontological discoveries were made there. The first fossilized iguanodon bones were found in Sussex by Gideon Mantell. His wife Mary was very helpful. Mantell published the description in 1825.
Iguanodon teeth (species Iguanodon anglicus) from the original description of Mantell, "Notice on the Iguanodon, a newly discovered fossil reptile, from the sandstone of Tilgate forest, in Sussex" (1825). The jaw and teeth of an iguana were drawn at the bottom for comparison.
In 1878, an important discovery of an entire iguanodon cemetery takes place in a mine ravine near the Belgian town of Bernissart. At a depth of 322 meters. As many as 38 well-preserved skeletons, some of which are almost complete. The fossils have greatly advanced research on iguanodontids. They are now on display at the Royal Institute of Natural Sciences in Belgium. New finds appear periodically in different parts of the world.
Body structure
The body length of the ornithopod reached 10 meters. The height is up to 5 m. Iguanodon weighed up to 3 tons.
He moved mainly on four legs, but he could walk on two. There are three thick toes on the hind feet.
The forelimbs are fairly well developed. Moreover, the structure of the hands is somewhat human-like. The middle three toes were strong and ended in flat hoof-like claws. They were used for support when moving. The flexible fifth finger served as a thumb for humans to grab objects (for example, when the iguanodon tilted branches or gnawed at the stems). A kind of "big pinky". But the most amazing finger is the first. It lacked intermediate joints, creating a sharp spike about 20 cm long! Most likely, its main purpose is a weapon of protection against predators. Perhaps they also used the iguanodon to drive away rivals in the herd or to use them to get special food.
A rigid tail, flattened from the sides, served as a classic support for balance.
The skull, vaguely similar to that of a horse, ended in a bony beak, with which the iguanodon plucked plants. Strong teeth, indeed like an iguana, were quite suitable for thorough chewing. There were 29 on the upper and 25 on the lower jaw.
Males were larger than females, which is observed in many modern animals.
Separately, it is worth telling about the history of body reconstructions, full of funny mistakes. In the very first reconstruction, the Mantella iguanodon looks like a baggy, squat iguana.
After all, then there was not even a faint idea of the ancient reptiles. The spine of the right toe has been interpreted as a horn on the nose. Then Louis Dollo reconstructed it as a purely two-legged animal. This is how Zdenek Burian portrayed him (illustration below).
It was only at the end of the 20th century that they came to the conclusion with certainty that the "iguana-toothed" combined means of transportation.
Iguanodon skeleton
The Iguanodon photo shows the Iguanodon bernissartensis exhibit (Transatlantic Ethnographic Museum Bremen, Germany).
We also bring to your attention a skull from the Royal Institute of Natural Sciences, located in Brussels, Belgium.
Nutrition and lifestyle
The remains of numerous groups in the Belgian Bernissar suggest with a degree of certainty that iguanodons lived in herds. Together they ate the lavish vegetation of the plains, including succulent horsetails and ferns.Some researchers write that, despite its large size, the ornithopod could move at a speed of 24 km / h, reaching it during bipedal running.
Iguanodons are large herbivorous dinosaurs from the group of ornithopod dinosaurs. The animal reached 9 meters in length and weighed more than 5 tons.
Iguanodons lived in the first half of the Cretaceous in Western Europe, North Africa, Mongolia and North America.
The Iguanodon's thigh is more birdlike in structure. In most dinosaurs, the hip structure is closer to the lizard's thigh. In this regard, at the beginning of the study, scientists made a mistake. In the beginning, the researchers attributed the skeleton to the remains of an unknown species of giant lizard.
Detailed descriptions of the Iguanodon have been made from more than one find. For the first time, the remains of the Iguanodon were discovered in England. Similar remains were unearthed in a coal mine in Belgium. From these findings, paleontologists now have an idea of the lifestyle and habits of this prehistoric animal.
The first find of Iguanodon bones, made in England, was discovered by the rural physician Gideon Mantel, who was fond of paleontology. He and his wife collected fossil bones in a quarry near a small town in the gravel of Sussex. A medical scientist came across several fossilized teeth of some prehistoric animal. The shape of the teeth was unusual - leaf-like. Fossilized bones were also found.
Scientists, who first examined the doctor's find, attributed the bones to the ancient, and the teeth - to. But the attentive village doctor questioned the paleontologists' claim. In the laboratory of a familiar zoologist, he saw a modern tooth. The found teeth of an unknown fossil animal were an exact copy of the teeth of an iguana, only many times smaller. Such a comparison made it possible to assert that the teeth of an ancient reptile were found. In 1825, the found parts of the skeleton were given the name "iguanodon", which means "iguanozub".
In Belgium, in the coal mines near the village of Bernissart in 1876, a whole Iguanodon cemetery was waiting to be explored. Completely intact remains were also found in the 39 Belgian skeletons found. The bones found were collected, prepared and mounted in a bipedal position at the Brussels Museum.
If we consider in detail the structure of the Iguanodons, the most interesting are its limbs. The legs of the animal are very similar to the clawed paws of a huge bird. There were five toes on the front paw, and three on the back. The iguanodon had a very large claw, which the English scientist Richard Owen initially mistook for a horn.
The structure of the Iguanodon's head is also curious. The beak (mouth) of the animal was similar to the beak of a modern parrot. With this beak, Iguanodon tore off the shoots of plants and leaves, while helping himself with the fingers of his forelimbs.
The animal had to maintain a large mass (about 5 tons) and spend the whole day in search of food.
Who found fossils now classified as Terasaurus en and Mantellodon en. As a result, the iguanodon became the second dinosaur after the Megalosaurus, which was named after the analysis of fossils. In addition, along with Megalosaurus and Hyleosaurus, he was the first to be called a dinosaur. The genus is part of a larger group called the iguanodonts. The taxonomy of the genus still raises numerous questions: throughout the history of the study, more and more species were attributed to it, and some species were subsequently assigned to other genera.
As scientists found more and more iguanodon fossils, more information about the genus became over time. Numerous specimens, including nearly complete skeletons found in two famous burials, have allowed paleontologists to understand many aspects of the animal's life: nutrition, mode of movement, and social organization. Also, as one of the first dinosaurs discovered, the iguanodon has occupied a small but rather prominent place in popular culture.
Iguanodons were large herbivorous dinosaurs that could move on both two and four legs. Representatives of the only species that undoubtedly belongs to the genus Iguanodons, I. bernissartensis, had an average weight of about 3 tons and an average body length of up to 10 meters, the length of some individuals reached 13 meters. They had large and narrow skulls, a beak made of keratin in the front of their jaw, followed by teeth similar to those of an iguana, but larger and more frequent.
The forelimbs were about a quarter shorter than the hind ones and ended in five-fingered hands, the three central fingers on them were adapted for support. The thumbs had spikes that were supposedly used for protection. At the beginning of the 19th century, these thorns were considered horns and were placed by paleontologists on the nose of an animal, their true position was revealed later. The little fingers, in contrast to all other fingers, were long and flexible. The fingers consisted of phalanges, organized according to the formula 2-3-3-2-4, that is, there were 2 phalanges on the thumb, 3 on the index finger, etc. The hind legs, which were adapted for walking, but not for running, had only three toes. The spine and tail were supported by tendons. These tendons have developed throughout the life of the animal and may ossify over time (ossified tendons are usually ignored in skeletal reconstruction and in drawings).
As its name suggests, the iguanodon's teeth were similar to those of an iguana, but were large. Unlike their related hadrosaurs, iguanodons have changed teeth only once in their entire life. The upper jaw had 29 teeth on each side, the premaxilla had no teeth, and the lower jaw had 25 teeth. The large difference between the number of teeth on the jaws was explained by the fact that the teeth on the lower jaw were much wider than on the upper. In addition, due to the deep rows of teeth and other anatomical features, it is believed that iguanodons had cheek-like formations that allowed them to hold food in their mouths.
Iguanodonts is also called a taxon, which includes numerous representatives of ornithischian dinosaurs that lived in the second half of the Jurassic and early Cretaceous. In addition to the iguanodons themselves, the taxon also includes Dryosaurs, Camptosaurs, Uranosaurs and Hadrosaurs. In early sources, the iguanodonts were called a full-fledged family, which acted as a so-called "garbage taxon": it included all representatives of ornithischian dinosaurs, which could not be attributed to either hipsilodonts or hadrosaurs. In fact, childbirth such as Callovosaurus, Camptosaurus, Craspedodon en, Kangnasaurus, Mochlodon, Muttaburrasaurus, Ouranosaurus and Probactrosaurus, as a rule, belonged to the iguanodont family.
With the advent of new research, it became clear that iguanodonts are not a family, but a paraphyletic group. In essence, the names iguanodon and iguanodon have come to be considered synonymous. A taxon such as iguanodonts is still used in the scientific literature, although most of the species traditionally assigned to it are now classified as hadrosaurs. In a cladogram, an iguanodon is usually placed between Camptosaurus and Hadrosaurus, suggesting its descent from their common ancestor. American paleontologist Jack Horner, based on the remains of skulls, advanced the theory that the hadrosaurid family split into two distinct subfamilies: Saurolophinae, which included flat-headed dinosaurs, including iguanodons, and Lambeosaurinae, in which the paleontologist included dinosaurs with a crest on their heads ... His theory did not meet with much support.
Iguanadon skeleton in a bipedal position. Part of the exposition of the Ubersee Museum in Bremen
Below is a cladogram compiled by Andrew McCall in 2012:
The first specimens of iguanodon remains were teeth that were exactly like herbivorous reptiles, although there has been a long debate over what the iguanodon actually ate. As Mantell noted, the remains he worked with did not resemble any modern reptile, especially the presence of a toothless, scoop-like symphysis on the lower jaw, which he still noticed on the skulls of giant sloths like mylodon en. He also suggested that the iguanodon had a long, tenacious tongue, with which the animal, like a giraffe, plucked leaves from trees. Later finds refuted this assumption, since the anatomy of the hyoid bone spoke in favor of a short and muscular tongue, which was convenient for moving food around the mouth when chewing.
The anatomy of the skull was such that the teeth of the upper jaw could rub against the teeth of the lower jaw, grinding food. Since the teeth changed regularly with abrasion, the iguanodon could use them to chew on tough plant material. In addition, the front teeth of iguanodons were absent both from above and below, and due to the bony nodes that formed an uneven edge on the jaws, scientists suggested that iguanodons had a keratin beak, which these dinosaurs could bite branches and shoots with. Also, the long and flexible little fingers on the forelimbs of the animal, unlike the rest of the fingers, could facilitate the extraction of plant food.
Iguanodon hand Part of the exhibition in Brussels
The exact diet of the iguanodon is unknown. Dinosaur sizes like I. bernissartensis gave them access to any food from ground level to 4-5 meters in height. David Norman hypothesized that iguanodons ate horsetails, cycads and conifers, although there is evidence to suggest a connection between the diet of this dinosaur and the early Cretaceous angiosperms. According to this hypothesis, due to the fact that iguanodons ate them, the first angiosperms grew very quickly, gradually replacing all other plants. However, unequivocal evidence of this has not yet been found. Regardless of its diet, the size of the iguanodon makes it the dominant medium to large herbivore in its ecosystem.
An image of an iguannodon standing on two legs and leaning on its tail. 19th century
The early fossils were only partially preserved, which made it possible only to speculate about the mode of movement and nature of the iguanodons. Initially, these dinosaurs were depicted as four-legged animals with a horn on their nose, but when more bones were found, Mantell noticed that the forelimbs of the iguanodon were noticeably shorter than the hind ones. His rival, Sir Richard Owen, held the theory that they were dinosaurs with four pillar-like legs. The first reconstructions of the iguanodon's appearance were first offered to lead Mantella, but he rejected this offer due to a sharp deterioration in health, so Owen's point of view eventually became dominant. After the discovery of a large number of skeletons near the Belgian city of Bernissart, scientists again reconsidered the way the iguanodon moved - now it was portrayed as a two-legged dinosaur, which rested on its tail like a kangaroo.
Subsequently, David Norman, re-examining the remains of the iguanodons, noticed that the animal could not lean on its tail in any way due to the fact that its spine was reinforced with ossified tendons, as a result of which the tail had to literally be broken in order to make it support. However, if we reconstruct the appearance of a dinosaur in the form of a four-legged, then many anatomical features of its skeleton become clear. For example, the forelimbs had three central toes grouped together, having phalanx-like hooves, which made it possible to transfer the weight of the front of the body to them at any time. The wrists were also relatively immobile, as were the forelimbs as a whole, as well as the shoulder blades. All this spoke in favor of the fact that the animal spent at least part of its life on four legs.
In addition, it is likely that the older the iguanodon was, the more often it moved on four legs, since its weight and size increased with age. The little ones I. bernissartensis had much shorter forelimbs (60% of hind limb length compared to 70-75% in adults). Also, when walking on four legs, judging by the found prints, the iguanodon rested only on his fingers, leaving his palms open. The iguanodon could reach speeds of up to 24 km / h, but only moving on two legs, since in a position on four legs he was not capable of gallop.
Large three-toed footprints have been found in early Cretaceous rock formations in England, but these footprints were difficult to interpret at first. Some authors originally associated them with dinosaurs. In 1846 E. Tagert suggested that these footprints belong to an iguanodon, and in 1854 Samuel Beckles noted that the footprints are very similar to the paw prints of birds, although he did not rule out that they could have been left by dinosaurs. After the complete skeleton of the hind limb of a young iguanodon was found in 1857, it became clear that traces could have been left by similar dinosaurs. Despite the fact that there is no direct evidence of this yet, it is believed that the tracks found belong to an iguanodon. In England, footprints have been found suggesting that the animal could move on four legs, but the prints are not well preserved to confirm this assumption. Similar traces have been found wherever iguanodon remains have been found.
One of the most famous features of the iguanodon is the thorn on the thumb of the forelimb. Mantell originally placed it on the nose, but when analyzing the remains found near Bernissart, Dollo moved the thorns to the right place, that is, to the thumbs. This was not the only time that the thumbs on the thumbs were initially placed in the wrong place: in the 1980s, in the reconstructions of the appearance of the noasaurus, baryonyx and megaraptor, the thumbs of the thumbs were mistakenly located on the hind limbs, as was the case in dromaeosaurids.
The most likely purpose of the thorns was considered protection from predators, however, there were suggestions that the iguanodon could use the thorn on his thumb to pluck fruit from trees or against his congener. It was also hypothesized that a poisonous gland was located in the area of the thumb, however, based on the fact that the thorn was not hollow and did not have grooves that allowed injecting poison, it was recognized as untenable.
While there is a theory that the iguanodons found near Bernissart died in one major cataclysm, it is generally accepted that they were all victims of a series of disasters. According to this interpretation, the iguanodons died in three disasters, and although all the skeletons were found in one place and died in a relatively short period (presumably from 10 to 100 years), there is no evidence that these dinosaurs were herd animals.
The main argument against herding is the remains of cubs, their location is very different from what can be seen, for example, as a result of the mass death of living species of herd animals. It is believed that they were victims of periodic floods, which often happened near lakes and in wetlands. However, Neden put forward a theory based on an analysis of the age of animals and the geography of their habitat that the iguanodons were gregarious and died during the migration process.
Unlike other dinosaurs, which were probably gregarious (in particular hadrosaurs and ceratopsids), for a long time there was no evidence of sexual dimorphism in iguanodons. There was a version that either I. "mantelli", or I. atherfieldensis (Dollodon and Mantellisaurus, respectively) and larger and more massive I. bernissartensis are representatives of the same species, but female and male, respectively. At the moment, this version has been declared untenable. According to an analysis carried out in 2017, it was found that individuals I. bernissartensis indeed, differences were observed in the structure of the limbs (scapula, humerus, thorn on the thumb, ilium, ischium, thigh, tibia) and the spine (axis, sacrum, caudal spine). In addition, the analysis showed that representatives of the species I. bernissartensis could be divided into two categories, depending on whether there were grooves in the caudal spine and the size of the spines on the thumbs.
A fracture was found in one of the iguanodon's pelvic bones. Two more individuals showed symptoms of osteoarthritis, as evidenced by the presence of osteophytes in the bones.
There is a widespread legend about the discovery of the iguanodon. According to her, in 1822, Gideon Mantell was summoned to a patient in the town of Cacfield en (Sussex, England) and while walking in Tilgate en forest, Mantell's wife, Mary Ann, who accompanied him on the trip, found iguanodon teeth in the local deposits. However, there is no evidence that Mantell visited patients with his wife, moreover, many years later, in 1851, he claimed that he found the teeth himself. However, some do not consider it a legend. Mantell's records also indicated that as early as 1820, he acquired large bones found in a quarry near Whiteman's Green. Since among the finds were the teeth of a theropod, that is, a predatory animal, Mantell began to restore its skeleton, as well as the skeleton of a giant crocodile. In 1821, Mantell noted the discovery of the teeth of a herbivorous animal and suggested the presence of the remains of a large herbivorous reptile in the sediments. However, in his article published in the magazine Fossils of the South Downs in 1822, Mantell did not yet consider the possibility that the teeth were somehow connected to his far from complete skeleton, but at the same time he suggested that he had two sets of remains: one belongs to a carnivorous species (“a huge animal from Lizard Tribe "), and the other - herbivore. In May 1822, the teeth of a herbivore were shown to members of the Royal Society of London, but those, including William Buckland, refused to recognize the find as the remains of an ancient animal, considering it the teeth of either a fish or a rhino. On June 23, 1823, Charles Lyell, during a party in Paris, showed some of the teeth to the famous French naturalist Georges Cuvier, but he also believed that they belonged to a rhinoceros. Although Cuvier took back his words the next day, Lyell chased away Mantell, who was unwilling to admit the obvious. In 1824, Buckland analyzed the remains of a Megalosaurus, after which he decided to take another look at the collection of Mantell finds. On March 6 of the same year, he admitted that they could belong to a giant lizard, although the scientist denied that it could be a herbivorous animal. Nevertheless, the inspired Mantell again sent some teeth to Georges Cuvier, and on June 22, 1824, he sent a letter in response, in which he informed that Mantell's find could belong to both a reptile and a giant herbivorous animal. In addition, Cuvier in his work Recherches sur les Ossemens Fossiles admitted his earlier mistake, which allowed Mantell to become part of the scientific community again. Subsequently, Mantell decided to support his theory with facts and began to look for parallels in the anatomy of modern reptiles. In September 1824, he visited the Royal College of Surgeons, but initially did not find anything similar to the teeth he found. However, he was soon approached by an assistant curator. Samuel Stachbury en, who noted that the teeth were very similar to those he had seen in an iguana, but only 20 times larger.
An iguanodon skeleton found at Maidstone is now classified as the remains of a Mantellodon
Based on isometric calculations, Mantell determined that the iguanodon had a body length of 18 meters, which was more than the body length of the Megalosaurus (12 meters). In addition, since the teeth he found were similar to those of an iguana, Mantell decided to name the dinosaur iguanodon (from “iguana” and ancient Greek. ὀδών "tooth") . Initially, the scientist wanted to call him an iguanosaur ("lizard iguana"), but his friend William Daniel Conyber en felt that such a name was more suitable for the iguana itself and suggested the options "iguanoid" ("like an iguana") and "iguanodon". However, Mantell forgot to add his last name to the chosen dinosaur generic name to get the traditional two-word Latin name. This error was corrected in 1829 by Friedrich Hall, who named the species Iguanodon anglicum, later the name was changed to Iguanodon anglicus .
In December 1824, officially giving the dinosaur a name, Mantell sent a request to the local Portsmouth Philosophical Society, in which he announced his discovery. On December 17, his letter was read at a meeting of the members of the society, and on December 20, a report of the meeting, in which the name of the dinosaur was written as “iguana a don ", was printed in Hampshire Telegraph... On February 10, 1825, during a report to the Royal Society of London, Mantell officially presented the results of his research.
In 1834, a fuller skeleton of an iguanodon-like raptor was found near Maidstone, Kent, England. After making sure that the found dinosaur has characteristic teeth, similar to those of an iguana, Mantell acquired this specimen for his personal collection of fossils. Mantell later used the Maidstone plate to reconstruct the appearance of a dinosaur, but due to the incompleteness of the skeleton, the scientist made several mistakes, in particular, he placed the thorn of the forelimb on the nose, mistaking it for a horn. The discovery of much better preserved specimens allowed these errors to be corrected. The skeleton now found in Maidstone, along with the slab in which it was found, is part of the collection of the London Natural History Museum. In addition, in 1949, the town of Maidstone, in which the slab was found, changed its coat of arms, adding an iguanodon as one of the shield holders. In 1832, the German paleontologist Hermann von Mayer renamed the Maidstone find to I. mantelli... It was subsequently determined that the Maidstone specimen, known as the "Mantell Plate" and officially marked as NHMUK 3741, was not an iguanodon. In 2012, MacDonald identified it as belonging to the genus Mantellisaurus, followed by Norman attributed it to the species Mantellisaurus atherfieldensis, and Paul used it as a holotype when examining the remains Mantellodon carpenteri .
At this time, tensions began to build between Mantell and Sir Richard Owen, an ambitious and much better-off scientist in terms of money and connections. Owen, as an ardent supporter of the theory of creationism, opposed the earlier versions of evolutionary theory ("transformism"). According to his descriptions, dinosaurs could not reach 61 meters in length, since they were nothing more than giant lizards; he also endowed them with features characteristic of mammals, which he attributed to God's creation; according to the science of that time, dinosaurs did not "transform" from reptiles to mammals.
A few years before his death, in 1849, Mantell realized that iguanodons were not massive and thick-skinned lizards, as Owen drew them, but had slender limbs. Nevertheless, health problems prevented him from directing the creation of the sculptures of the Crystal Palace (pavilion of the first World Exhibition in London in 1851), as a result of which Owen's point of view was entrenched for many decades. Together with Benjamin Waterhouse Hawkins en Owen created from concrete and steel frame about a dozen figures of various prehistoric animals, including two iguanodons (created from the skeleton of a mantellodon): one in a standing position on four legs, the other - lying on his stomach. A banquet for 20 people was organized inside the sculpture of a standing iguanodon.
The most famous find. associated with iguanodons, was discovered on February 28, 1878 near the Belgian commune of Bernissart in a mine 322 meters deep. Two miners, Jules Creter and Alphonse Blanchard, struck several times with a pickaxe on what was initially mistaken for petrified wood. On May 15, 1878, Louis de Pauw, with the support of Alphonse Briard, a mine superintendent from Morlanvels, began excavations, and in 1882 the paleontologist Louis Dollot reconstructed the skeletons found. They were virtually the most complete iguanodon skeletons ever found. In addition to them, the remains of plants and fish, as well as other reptiles (for example, crocodiloforms en Bernissartia en). The remains of at least 38 iguanodon specimens were recovered, most of which were adults. Many of the remains found were attributed to a new species called I. bernissartensis, whose representatives were larger and more massive than those found in England; one specimen, lighter and more graceful, was identified as I. mantelli(now known as Mantellisaurus atherfieldensis). In the same 1882, a typical specimen of a fully restored skeleton was presented to the general public. I. bernissartensis... The exhibit was placed in the chapel of the Palace of Charles of Lorraine and, using a special system of ropes and blocks, was given the pose of a living dinosaur. In July 1883, this skeleton, along with some others, became part of an exhibition organized in the courtyard of the palace, and in 1891 it was transferred to the Royal Museum of Natural History, of which it is still a part of the exposition (9 skeletons of iguanodons are constantly on display, 19 more are kept in the basement of the museum) ... There are also exact copies of these skeletons among the exhibits in en and Cambridge Museum them. A. Sedgwick en.
Since at that time paleontologists thought little about the safety of the remains, they soon encountered the so-called "pyrite disease". While the remains were in the ground, due to the surrounding damp clay and lack of access to oxygen, they could lie there for many years, but after they got into the air, the pyrite in them oxidized, turning into iron sulfate, as a result of which the fossils became brittle and easily crumbled. To avoid this, scientists had to come up with ways to preserve the remains as needed. De Pauw, when extracting Bernissar finds right in the mine, dipped them into raw clay, wrapped them in paper and gypsum and, using iron rims, formed about 600 blocks with a total weight of 130 tons, prepared them for further transportation to Brussels. After delivering the blocks, he removed the wrapping, boiled the bones in gelatin mixed with clove oil to rid them of pyrite deposits, and then covered the remains with glue and foil. The missing bones were recreated using papier-mâché. However, this method had an unforeseen side effect: due to the fact that moisture remained inside the fossils, the rate of their destruction increased markedly. In 1932, the director of the Royal Museum of Natural History, Victor van Stralen, decided that the Bernissar specimens needed to go through a new stage of processing in order to better preserve them. From December 1935 to August 1936, museum staff considered the possibility of using alcohol, arsenic and 390 kilograms of shellac for this. Alcohol helped the mixture penetrate deep into the pores of the bones, arsenic did not let them lose their shape, and shellac made them stronger. From 2003 to May 2007, the fossils went through the third stage of processing: traces of shellac, glue and gelatin were removed from them, after which they were impregnated with a mixture of polyvinyl acetate, cyanoacryalate and epoxy glue. Today, the preservation of the remains is maintained either through environmental monitoring systems, or - if these are recently found remains - they are impregnated with polyethylene glycol, heated by a vacuum pump, in order to remove all moisture from the pores, seal them and strengthen the remains.
Dollo, when restoring the skeletons, came to the conclusion that the idea of iguanodons as simply huge thick-skinned lizards, based on the point of view of Sir Richard Owen, was largely incorrect. In particular, the scientist reconstructed these dinosaurs as two-legged, not four-legged creatures, and he took the anatomy of cassowaries and wallabies as a model; he also transferred the thorns from the nose of the iguanodon to the thumbs of the forelimbs of the dinosaur. Its reconstruction also contained mistakes made under the influence of the ideas of the past years. So, despite the fact that the remains found near Bernissard had a straight tail and ossified tendons are noticeable, Dollo added a noticeable bend to the tail spine, characteristic of kangaroo. In fact, in order for the tail to take this position, it literally had to be broken. In the case of the correct body position, that is, with a straight tail and back, the animal moved parallel to the ground, keeping its front limbs at the ready, so that at any time to transfer weight to them.
In 1881, excavations were stopped, despite the fact that at that time not all of the remains had been recovered from the mine. With the outbreak of the First World War, after Bernissar was captured by German troops, a paleontologist was invited from Berlin
Iguanodons, representatives of a group of herbivorous dinosaurs, lived on Earth about 100 million years ago. And these giant animals inhabited the territory of modern Europe. The lizards had teeth similar in appearance to the teeth of the now known iguanas lizards. That is why prehistoric animals got their name. The huge dinosaur teeth were arranged in 4 - 5 rows, each of which seemed to be impaled on the adjacent one. The fact is that as a result of eating a huge amount of various plant foods, the teeth of the animal wore out very quickly, deteriorated and therefore were constantly replaced by new ones, growing one above the other. It is this reason that can explain such an unusual structure of the teeth of iguanodons.
Thanks to the findings of paleontologists, naturalists are inclined to believe that the diet of giant iguanodon lizards was represented mainly by branches and green shoots of araucaria and coniferous trees, which were widespread in Europe during the Mesozoic. Judging by the discovered remains, the height of the iguanodons did not exceed 5 m, and the body length was 10 m. These giant animals could move on both two and all four legs. At the same time, the hind limbs of the raptor were much larger in size and more powerful than the front ones, which were poorly developed. The front and hind legs ended in flattened and wide toes. It was they who helped the animals move around the swampy swampy terrain. On the front paws there were five toes. At the same time, the thumb was longer than the others and ended with a sharp and long claw, which apparently served as a means of protection from enemies. Iguanodons had a long and powerful tail, which, according to scientists, also helped the animals to move.
According to modern naturalists, iguanodons led a herd lifestyle. They lived in dense thickets of trees, located on the shores of shallow water bodies. It was water that served the lizards both as a source of food, and often as a place of shelter from a predator.
IguanodonFor the first time, the skeleton of an iguanodon was discovered in 1818 in England. It was found by the famous paleontologist G. Mentel. The event became especially remarkable also because it turned out to be the first in the history of paleontology to find the skeleton of the so-called terrible lizard. Having collected all the bones of the skeleton together, Mentel doubted the purpose of one of them, which in appearance resembled a horn, and therefore attached by scientists to the nose of the skull. Later it turned out that in fact it was the toe of the front paw, with which the lizard defended itself when attacked by enemies.
On New Year's Eve, 1854, the image of the first open dinosaur - the iguanodon - was used as a kind of tent decoration, placed over the festive table.
Fossil in paleontology is called the fossilized remains of animals and plants. Often the animals found themselves buried under thick layers of silt, sand, or ash. Gradually, the soft tissues rotted, and the hard ones could persist for several million years.
