The oldest giant dinosaur species has been discovered

SOUTHEAST OF THE PROVINCE OF SAN JUAN

The oldest giant dinosaur species has been discovered

Argentine researchers have presented Ingentia prima, the first giant dinosaur that inhabited the planet there are more than 200 million years. It exceeds three times the size of the largest Triassic dinosaurs known to date. The discovery was made at the Balde de Leyes depot in the province of San Juan.

Dr. Cecilia Apaldetti with a drawing of what the dinosaur was like Ingentia prima. Illustration Jorge A. González
Source: Agencia CTyS-UNLaM

Dinosaurs were not always giants. The history of evolution has taken millions of years for some species to double the weight of a current elephant and reach between eight and ten meters long, but this time was much less that it was believed: hence the great importance of the discovery of Ingentia premium, which would have had a body mass of up to ten tons.

Dr. Cecilia Apaldetti, a researcher at the Institute and Museum of Natural Sciences of the University of San Juan (IMCN) and CONICET, said that "this new species shows a growth strategy unknown until now and indicates that the origin of gigantism This has happened much earlier than expected. "

"Before this discovery, gigantism was considered to have arisen during the Jurassic period, about 180 million years ago, but Ingentia prima lived at the end of the Triassic, between 210 and 205 million years ago. ; years. " main study published in the prestigious journal Nature Ecology & Evolution.

Dr. Ricardo Martínez, also researcher of the RCIME and co-author of the publication, commented that "the name of this new species, " Ingentia & # 39; refers to its colossal size, while ] "prima" indicates that it is the first giant known to date on the planet. "

"Giant, especially, for his moment of evolution," Apaldetti remarked. He added: "We see in Ingenua prima the origin of gigantism, the first steps for that, more than 100 million years later, 70-ton sauropods could emerge as those who lived in Patagonia ".

The largest quadruped and large-necked herbivorous dinosaurs, such as Patagotitan, Puertasaurus and Argentinosaurus, derived from the sauropodomorphs of the Triassic as Ingentia prima; What was not known, until now, is that gigantism had already developed over 200 million years ago.

million. Ignacio Cerda, researcher at the Institute of Research in Paleobiology and Geology of the National University of Rio Negro (IIPG-CONICET, UNRN), analyzed the bones of this new species to understand how it grew in life : "Al As you can see in a growing season of trees, Ingentia prima bone cuts show cyclical seasonal growth, but what is striking is that the type of tissue deposited in the during these periods of growth is different from the other sauropods we knew until now ".

"This cloth allowed him to achieve very rapid growth," said Cerda. And he explained: "To differentiate the form of growth that he had, we can make an analogy with a car that continues at a continuous high speed, 100 kilometers per hour, imagining that it is so that the sauródopos grew, while the Ingentia prima was part of the trek at 300 km / h, during the growing seasons, to stop later during the winter or scarcity seasons and later, for push back to 300 kilometers per hour ".

Cyclic growth was common among the primitive sauropodomorphs of the Triassic, but no other species exceeded three meters in length and three tons of body mass. "The difference is that the tissue that formed in the rest of these sauropodomorphs did not have such a fast deposition rate," said Dr. Cerda, who also works at the Provincial Museum Carlos Ameghino at Cipolletti.

Although these growth rings may be observed in resemblance to trees, it is not possible to know the exact age at which this specimen died. "In this case, it is difficult to trace the continuity of the concentric lines, but we estimate that he was a sub-adult individual, who was still developing, so he could have grown a little more," said the researcher of the IIPG-CONICET. .

The first giant in the world already has a family
Beyond the fact that Ingenua prima, the first dinosaur to reach gigantism, was far from reaching the 70 tons that possessed the most giant sauropods at the end of the Cretaceous, the rate of accumulation of Bony tissue was not only superior to species of its time, but also larger than the largest giants that inhabited Patagonia.

Dr. Diego Pol of the Museum Egidio Feruglio (MEF) and CONICET, who was one of the authors of the study who presented the largest known dinosaur -Patagotitan-, also participated in the analysis of Ingentia prima to determine their relationship with other species already known.

"What we demonstrate is the existence of a family that had not been recognized, of which Ingentia prima is part, a species of South Africa. and another from South America, proving once again the close connection between the two continents at that time when everyone formed a supercontinent called Pangea, "said Dr. Pol.

The MEF researcher added that "the discovery of this new species of the Triassic has a great implication for the history of evolution because it corresponds to the first stage of the dinosaurs and it is important to know that, by the time they started to spread around the world, the first gigantic species have already appeared. "

"This finding gives a new look at the magnitude of the explosion of evolution that dinosaurs had," said paleontologist Pol, adding, "This evolutionary explosion was so great that She explains the success of the dinosaurs during the rest of her time. "

Giantism is an evolutionary survival strategy, especially for herbivorous animals, because size is a form of defense against predators. "In order to achieve gigantism, Ingentia prima has also had to adapt its physiology and develop an efficient food device to cover the energy needs of an animal of this size," Pol said.

An extraordinary site of the late Triassic

Researchers from the Institute and the Museum of Natural Sciences of the University of San Juan have the privilege of having in their province the famous site of Ischigualasto, l '. one of the most important of the Triassic in the world. As if that were not enough, a few years ago, they discovered the extraordinary location of the Bucket of Laws in the Marayes Basin, with which they can complete the puzzle of the first time of the dinosaurs.

Dr. Ricardo Martínez commented that "Bucket of Laws is a new site with an unknown fauna up to now, while in Ischigualasto we have a succession of Triassic rocks between 250 and 213 million years ago. 39 years, in this new site we have 235 million years until the end of the Triassic and even the first stage of the Jurassic period ".

In Balde de Leyes, in addition to discovering the herbivore giant Ingentia prima, they also found and named the carnivore Lucianovenator bonoi. "Lucianovenator and Ingentia are from the same period," said Martínez. And he analyzed: "Although Lucianavenator was not very big, because it measured a meter and a half, it was a caring bug and could have been feeding from Ingentia, maybe doing a group attack or take advantage of one of these wounded giants "

"However, we also found teeth that belong to a carnivore with a skull between 60 and 80 centimeters, so we know that there was a larger predator encircling there and that he would have could be a theropod or a predecessor of crocodiles, "added the researcher.

With each new campaign, more and more species and groups continue to appear. With regard to the environment of the time, Martínez said: "The temperature was higher and the weather varied a lot between the seasons, while in the meantime, although we did not find any Fossil remains of flora in the Balde de Leyes, we know that if Ingentia, a large herbivore, lived, there must be enough vegetation to feed it. "

The site was a kind of savannah at the end of the Triassic. In addition to the dinosaurs that were discovered, there were also giant iguanas, turtles and lauchite-shaped species, which could be related to the origin of mammals.

However, with the approach of the late Triassic, the environment became more arid, which provoked a series of extinctions that culminated 200 million years ago, after what new species will appear in the Jurassic. All this information has been preserved in the rocks of the new site and will be revealed by future campaigns and research.

Related Images

A few years ago, researchers discovered the extraordinary city of Bucket of Laws in the Marayes Basin, with which they can complete the puzzle of the first time dinosaurs.

Source: Agencia CTyS-UNLaM