Little time? At the end of the text there is a summary.
An American-South African research team unearthed remains of an unusually small relative of the T-Rex in Utah. The find closes a gap in the fossil record of the Tyrannosauroidea, which belong to the today most well-known predatory dinosaurs. They lived in the time frame of 165 to 66 million years exclusively on the northern continents. The first description of the newly discovered species Moros intrepidus, which was said to have lived about 97 million years ago, appears in the current issue of Nature Communications Biology.
What seems unusual to the layman on this Moros: He was a flyweight. Outwardly unmistakably a predatory dinosaur, he probably brought just under 78 pounds on the scales.
Fans of the "Jurassic Park" would claim him as a petite "Raptor": nimble, rather slim and small predators, which most likely hunted mostly in the pack. Sprinter, Renner and Reißer were, not heavyweight fighting machines. More wolves than tigers, but so agile and deadly that they probably became dangerous to prey animals that were many times heavier than themselves.
The six-member research team led by Lindsay E. Zanno now describes the newly discovered species based on graceful leg bones and teeth that were buried on a muddy, long-lost shoreline in what is now very dry Utah. The finds showed enough clear characteristics to be able to assign them to a specific family of predatory dinosaurs. The Moros intrepidus, the researchers are certain, definitely belonged to the Tyrannosauroidea.
And she knows every child as a terrifying predator of immense size. Little Moros, say his discoverers, is the oldest known representative of the family in the Cretaceous. At the end of his most prominent and last descendant, the Tyrannosaurus rex, at the top of the food chain in today's North America.
Until the middle of the Cretaceous, the ancestors of T-Rex were at most medium sized, in the Jura even rather small: The ecological niches for large-raptors were occupied in the northern hemisphere of Allosaurians and others. Although Allosauroidea looked quite similar to the later T-Rex, they were only very widely related to the Tyrannosauroidea: The two evolutionary lines, which included many different species, separated more than 160 million years ago.
Gigantism: Why this growth in size?
Allosauroidea quickly grew into giants. On the other hand, early tyrannosauroids put on speed, not strength and size. Only when the allosaurs became extinct they took their place - and quickly developed enormous sizes that were no longer surpassed by predatory dinosaurs in the northern hemisphere.
One might ask, why actually: For many millions of years Tyrannosauroidea with their speed-based hunting strategy were obviously highly successful. The question of the causes of gigantism in dinosaurs has been driving researchers since their discovery. Most lines of development showed a tendency to increase in size.
DPA
Lucky: Moros' greatest descendant, the T-Rex, has never met anyone. The species lived for only three million years at the end of the Cretaceous. In the picture: The Paleo showroom of Singapore Zoo.
Meanwhile, one believes to have found an answer to the question of the reasons for it. The Bonn paleontologist Martin Sander, who researched the gigantism of sauropods ("long-necked dinosaurs"), holds great importance for value. When choosing a partner, large animals would be preferred, which would be evolutionary. Size protect the herbivore from predators.
Carnivores, on the other hand, became more and more of a source of growth due to their increasing growth - large herbivores meant a lot of prey. But only those who could grow big enough could reach them. This is true even if it is assumed that large Tyrannosauroidea in their adult form could have been scavengers. Here, too, their size would have made a literally huge food supply usable.
Why Gigantism Saurians was physically possible at all, while mammals apparently can not become so big, we now know: dinosaurs breathed like birds, which are indeed their last living descendants. They had a lung apparatus that could process oxygen much more effectively. But that goes hand in hand with a significantly higher metabolism. One can answer the question of the reasons for the giant growth so very casually: they grew because they could. Their bodies were prepared to spend a lot of energy and grow rapidly.
Ten questions: What not everyone knows about T-Rex
Why are there hardly any "youthful" T-Rex finds?
With just over 30, some fairly complete skeletal finds T-Rex is one of the best documented dinosaurs. However, there are extremely few medium-sized, "juvenile" animal finds. The possible explanation: Juvenile T-Rex could have lived significantly differently than their parent animals - as fast, hunting raptors in packs. Their risk of dying, researchers believe, may have been lower than that of the very small or the full-blown force dumplings, who then engage in other confrontations. This could explain why very young and very old animals died more frequently (and fossilized) than the stable middle.
Was T-Rex hunter or scavenger now?
The question of how exactly T-Rex was nourished - as with many other large-raptors - hotly controversial. There are indications that he was a hunter and others who indicate that he was eating carrion. Perhaps both are true, and perhaps in different ages in different weighting: Mature T-Rex were extremely strong, but probably no fast, persevering runners. Her youthful forms were agile raptors that possibly hunted in packs. Maybe there is the answer: T-Rex hunted, if and as long as he could - and otherwise ate what came on the "table". Everything.
How did T-Rex get so big?
The answer to that is amazing: first of all not - and then very, very fast. In fact, it can be proven from fossil finds that T-Rex-boys remained relatively small until the age of about 14 years. Then her "puberty" set in - with an unprecedented spurt of growth in which they multiplied their body mass within two or three years. This indicates that they also had different ways of life in different ages (see above). In fact, juvenile animals differ so much from the ancients that they repeatedly misinterpreted fossil finds of young T-Rex as their own species of raptor.
Is it true that T-Rex was feathered?
It is currently fashionable to display even large raptors with plumage. It is true that many small raptors were feathered - the birds are descendants of Maniraptora, the crossings between the predatory dinosaur and the bird were fluent. It is also true that above all Chinese finds of small and medium-sized raptors show traces of protofedern. What you have not found so far: A large representative of the Tyrannosauroidea, where you could prove that. The rare skin findings, which are known so far, show a lizard-like scaling. Which does not exclude that young animals were feathered or adult animals wore individual show feathers. Conclusion: you do not know for sure, but it is not very likely at T-Rex.
How hard was T-Rex really?
Estimating the weight of a living creature that died out 66 million years ago is hard. Different experts come to very different results: T-Rex estimates range from six to 14 tons. Where you land depends not only on how thick and round the animal is reconstructed. For example, it is known today that Tyrannosauroidea were comparatively lightly built - and because of their bones: they were hollow, just like birds, their closest relatives. Estimates tend to be lower for most dinosaurs today than they were a few decades ago. T-Rex sees most researchers today at seven to nine tons.
Was T-Rex really the "king" among the predators?
Tyrannosauroidea were the largest raptors of the northern hemisphere. But the most spectacular discoveries are made today on the other side of the world. The largest predatory predators known today lived in Africa and South America and were only very distantly related to T-Rex. Both the "South Americans" like Mapusaurus or Giganotosaurus, as well as the African Carcharodontosaurus were a bit longer and taller than T-Rex. The largest of them all, Spinosaurus aegyptiacus, may have been a bit heavier, but did not always have to carry that weight - he lived and probably hunted half-aquatic.
Why do predators all look so much the same?
T-Rex was the first large, two-legged predatory dinosaur that became widely known and popular (other, earlier findings were first falsely reconstructed four-legged). What was then found on raptors, he always looked quite similar: comparatively small arms, strong hind legs, upright gait and a rather large head are part of the basic plan of all predatory dinosaurs (Theropoda). This comes very close to the original physique of the very first dinosaurs. The predatory dinosaurs varied it only in the details - for experts, however, there are many differences between the different branches of the evolutionary "bush" of Theropoda. They are similar in size to the birds, whose basic plan is always the same. Nevertheless, no one would think of describing a humming bird as "a vulture".
In Libra or upright: How did T-Rex really work?
In 1865, the American naturalist Joseph Leidys painted a picture that showed his idea of Hadrosaurus: standing tall and his tail supporting the body. It was to characterize the ideas of bipedal dinosaurs until the 1970s. But no two-legged dinosaur stood or moved like that. What is correct is today's presentation of such animals, in which the head and tail form a balance that balances the weight perfectly. One can imagine how quickly such animals could move as they leaned forward and pushed off the ground - it is a more "alive" idea in every sense than the Godzilla-tapping regressions. How do you know that? Only in Libra do the joints of the bones really fit together. In addition, there were thousands of fossilized dinosaur tracks - and never the slip track of a Dino tail.
Did T-Rex make a difference between male and female?
But surely - only if we had perceived that too, one does not really know. For a long time it was thought possible to differentiate between two "types": a "robust", larger one, interpreted as a female, and a graceful body shape. But there could also have been two subspecies, or the graces were not fully grown. Only the gender of a single fossil is known, because calcium was found in the body - the building material for eggs. But size would not have been the only way to be widely recognized as males or females - tones, smells, color or decorative elements such as show feathers or colorful throat sacks would also be conceivable. The problem with it is that something does not petrify, or only very, very rarely. Ergo: We do not really know.
When will it be possible to clone a T-Rex from a chicken?
At 11.30? Nonsense, it is already clear: But the question is almost as nonsensical as the answer. The world premiere came in 2009 through paleontologist Jack Horner. He proposed the "re-creation" of a "chickenosaur" by gene manipulation of birds: Horner wants to reactivate archaic "Dino genes" and thus to develop a bird back to a kind of dinosaur. He has been able to report minor successes ("dino-snout", "dino-legs"), which the story in the press held, but a chicken T-Rex will remain sci-fi: chicken and T-Rex are related, but the T-Rex is by no means an ancestor of the chicken - more like a great-great cousin of the second line.The answer to the T-Rex question is therefore definitely: never.Horner can one day with a cackling Maniraptor- Chicken comes from chasing corn and rye.
The fact that the Tyrannosauroidea finally went this way, was probably due to the fact that the ecological niche for large-raptors was freed by the extinction of competitors. The fact that no niche in the biotope remains unoccupied for a long time seems to belong to the basic rules of life: where space and food are, life also spreads.
The triumph of Tyrannosauroidea: late, but in a hurry
How fast this development from the small-Raptor to the predatory giant then must have happened , now shows Moros intrepidus . Although research now knows many early as well as late Tyrannosauroidea, there is a whopping, 70 million year gap between the fossil finds of the different size classes. So far, only a few intermediate steps have been found between the early Little T-Rexians and their gigantic descendants - so it could have been assumed that the size increase in the Cretaceous was gradual.
Moros now shows that there were about 15 million years longer than previously thought "small" Tyrannosauroidea. If that's true, then those approximately 70 million years of their development remained small Hatzjäger, who then made it only in the last 30 million years of their existence, their mass to hundred thirty times: estimates of the weight of the largest T-Rex vary between seven and fourteen tons ,
But Moros is not only interesting because it shows how late this development started. He also connects the populations and species in today's North America with those in Asia - the little tyrant shows traits that you can find over there. Its discoverers suspect last intercontinental contacts at a time when the mighty continent Laurasia just crumbled into its still existing parts of North America and Eurasia.
In summary, paleontologists discovered the fossil of an unusually small T-Rex relative in Utah. The approximately 97 million years old finds indicate that animals from the family of Tyrannosauridae spawned late large growth forms. Physical features connect the find Moros intrepedus with related animals in Asia.