A forgotten tooth in the body of a vegetarian dinosaur that escaped the bite of the T-Rex's tail is conclusive proof that T-Rexs killed their prey themselves
Tyrannosaurus rex, the most popular dinosaur among children and movie makers was the most brutal and efficient killing machine to walk the earth during the dinosaur era.
For over a hundred years paleontologists have argued whether Tyrannosaurus rex was a scavenger and not a true carnivore like today's birds of prey and not carnivores like lions. The lack of solid fossil proof that Tyrannosaurus was a carnivore has caused debate among scientists - until now.
"The T-Rex was the monster from our nightmares," says David Burnham, a vertebrate expert at the Institute for Biological Diversity at the University of Kansas. "However, since it was discovered in Montana and earned its nickname at the beginning of the 20th century, the debate has revolved around whether these large meat eaters were scavengers or carnivores. Most humans estimate that they were carnivores, but the scientific evidence that they were carnivores was quite elusive. It is true that they found many dinosaur skeletons with teeth marks that someone made, but what was the real victim? It was clear that these meat eaters were feeding on other dinosaurs, but were those dinosaurs alive or dead. This is what the debate revolved around. We did not find the proof that he hunted and killed."
Now, Borham is a partner in a team that has uncovered physical "smoking gun" proof that T. Rex was indeed a hunter-killer in the Hell Creek Formation of South Dakota. Borham and his colleagues discovered a T. rex tooth inside a fossilized spine of the herbivorous dreosaur that appeared to have survived the attack. The team described the findings in the current issue of the journal PNAS.
Burnham's research partners were Bruce Rothschild and the now-deceased Larry Martin, along with his former student Robert De Palma of the Natural History Museum in Palm Beach, and Peter Larson of the Black Hill Geological Survey.
"Robert De Palma was a student here at the University of Kansas who wrote his master's thesis on the Hell Creek Formation," says Burnham. "He found a fossilized tail of the dresaurus that seemed to grow abnormally. He came to me and said "what do you think caused this"? We cleaned the fossil and it was possible to see a tooth embedded in one of the vertebrae of the barbaz-like dinosaur. When we went to Lawrence Hospital and used CT to see the bones, we saw all the teeth."
Previous evidence of prey included T. rex fossils with preserved stomach contents and bones of ceratopsians (Triassic reptiles or something like that). However, there was no evidence as to whether the creatures were alive or dead when the T-Rex devoured them.
In contrast, says Burnham, the teeth of the unlucky creature that remained in the victim's body, after a careful examination of the teeth proved that they were the teeth of a T. rex. "We know that the T-rex bit the hadrosaur, but we also know that it managed to get away because the bitten area started to heal. It is possible that he was chased by the Tyrosaurus while it bit him and he luckily managed to escape. Our luck was to find the fossil with the proof."
By the way Tyrannosaurus Rex is apparently safe. He came out of this encounter hungry, and the tooth grew back as it did for any fallen Tyrannosaurus tooth.
Borham compares the situation to a lion chasing herbivores in the savannah. He cannot prey on the zebras or antelopes that are in the herd and he prefers to look for weak and slow individuals. That was probably the case in this case.
It should be noted that a student at the University of Kansas, Barnum Brown, was the one who discovered the first Tyrannosaurus Rex in 1900.
to the notice of the researchers
More on the subject on the science website
- Soft tissue remains of Tyrannosaurus rex were found
- Organic remains from 160 million year old dinosaur embryos
- A dinosaur, a relative of the T-Rex was the largest feathered creature
- The consensus is growing that an asteroid killed the dinosaurs
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Skeptic - I gave the hippopotamus as an example of a vegetarian animal that is capable of attacking other animals. Therefore, finding a fossil of an animal with a hippopotamus tusk would not indicate that the hippopotamus fed on meat. The data you wrote about the aggression of the rhinoceros and the hippopotamus only strengthens my claim - it is not possible to draw the conclusions that the researchers wanted to draw from the findings in the article.
Jotham:
1) The article is as decisive as the title. In the subtitle the finding is described as "conclusive proof" and in the article itself as a "smoking gun".
2) Regarding sections 1 and 2: I agree with you, I never disputed the fact that T-Rex feeds on meat, but only the conclusion drawn by the researchers from the findings described in the article.
3) You claim that it can be concluded from an event where a T-Rex sank its teeth into live prey that it has the ability to prey, if only on some level. I think all that can be concluded from this is that the two animals came into conflict, and this could have happened for a million and one reasons. And that leads me to your claims about the statistical considerations.
4) You made several claims, I will address them in order:
A. "When you discover a fossil you have to use statistical considerations. What are the chances that the find describes a very rare event?" - I agree with the claim.
B. "The very fact that you found the fossil increases the likelihood that the fossil represents a not rare event" - the claim is wrong. The mere fact that I have observed an event does not say anything about the probability that it will happen. Let's say I roll a die now 100 times. The chance of getting this particular sequence is 1 in 6 to the power of 100. Does the fact that I specifically threw a certain sequence teach us anything about the probability of getting that sequence? Is the chance of receiving such a sequence lower just because we watched it? The answer is negative.
third. "It is very unlikely that relatively many teeth, or teeth marks of Tyrax were found in other dinosaurs and everything in Fox" - you are confusing two things. Many evidences have been found that the T-Rex fed on meat - tooth marks in the fossils of other dinosaurs, remains of dinosaurs in its stomach, etc. But there is only one evidence that he attacked a living dinosaur - and that is the evidence described in the article. Based on this one and only testimony, the researchers seek to draw conclusions regarding the behavior of the entire species, ie that it actively hunted its prey and did not prey on carrion. This is a wrong conclusion.
d. "A case of a hippopotamus preying on another animal is very rare, and the chance of it being discovered in paleontological findings is zero." - The case is not so rare, the hippopotamus is an aggressive animal that tends to attack various animals, including humans. On rare occasions, it is even nourished by the same interests that it has valid. I have no idea what the chances are that this will be discovered in paleontological findings, and I don't understand what you are basing your claim on that the chances are zero. In any case, the fact that vegetarian animals are able to systematically attack other animals shows you that it cannot be concluded that it is a carnivorous animal.
Tyrannosaurus and/or Tyrannosaurus definitely had the right anatomical structure to be a carnivore. He had a big mouth and big sharp and huge teeth whose every bite was worth about 325,000 pounds of weight which proves that they are carnivores. One of the reasons for studying the science of dinosaurs is to gather comprehensive information to find reasons for their extinction in the past. Not long ago I read an article about giant flea fossils that were found. There is a theory that perhaps one of the main reasons for the extinction of dinosaurs is indeed because of this reason. Why is it important for us to know? Use your imagination?
If there is already proof here, it is the proof of the sparseness of thought of certain researchers...
It is not at all clear what proof they found, and what the smoking gun is.
So let's say they found a tooth of one animal inside the body of the other animal,
What it means?
that they fought, and one bit the other.
Beauty.
But from here to bring evidence that the biter is also a predator?
Haven't you heard of humans biting each other?
And of course animals bite each other...
Even without devouring them...
Why would the drosaur approach Tyrannosaurus and threaten him?
If the tyrex has the ability to catch the drosaur, and the tyrex eats meat, then there is no reason why it wouldn't devour it.
A complete response to the article.
It could very well be the case that the T-Rex felt threatened and therefore defended itself, but to jump to the conclusion that it is a predator, and does not eat carrion with such determination is a bit crazy...
Newton was a mathematician and astronomer. He tried to find a regularity for the heavenly bodies. As part of the research he discovered a regularity that fits many things that surround us, but this was not his initial goal. If you refer to the purpose of his research, you can ask "How will finding laws for the movement of the sun and the stars help me on a daily basis?".
First of all, I am sure that the title of the article here is very decisive to attract readers.
Many times in the press scientific findings are interpreted too decisively (at best).
One can guess that the scientists who discovered the tooth are aware of the uncertainty of their find, and of every find of this kind.
Response to Lior:
1) You can tell that Tyrax eats meat just by its anatomy.
2) Tyrrhex teeth and tooth marks have been found in the fossils of other dinosaurs already in the past. So the question is if the tirax eats carrion or if it is a carnivore.
3) If an event was discovered in which Tyrax sank his teeth into a living dinosaur, which was also healthy enough to escape and recover, it means that Tyrax has the physical ability to devour at one level or another.
4) When you discover a fossil you have to use statistical considerations. What are the chances that the find describes a very rare event? The very fact that you found the fossil increases the likelihood that the fossil represents a not uncommon event. It is very unlikely that relatively many teeth, or teeth marks of Tyrax were found in other dinosaurs and all in Fox. You might also expect that finding a Tyrrhex tooth in a dinosaur that managed to escape and recover would be an even rarer event, yet such a fossil is found. A case of a hippopotamus preying on another animal is very rare, and the chance of it being discovered in paleontological findings is zero.
Exactly what Lior said...
It is simply delusional, delusional that a scientist makes a statement based on a finding or lack of a finding.
Those who claim that the T-Rex eats carrion based on a lack of finds and those who claim that the Tyrannosaurus hunted based on a single find, are showing such great arrogance that it is simply embarrassing.
Tomorrow a scientist will see someone who looks quite similar to you and prove to you that you don't have a sister.
And regarding the counter example given by Yotam Lashimi, about Newton who researched the laws of mechanics, I am pretty sure that Newton did not walk down the street, see a stone covered in blood and ask himself "I wonder if this stone was thrown at someone on purpose or by mistake" and publish a journal about it.
And I'm pretty sure that "does a T-Rex hunt or eat scavengers?" You will not affect the laws of heredity and medicine or the speed of your internet surfing.
For shimmy:
Human curiosity is what brought us this far.
Lior
According to my memory, the hippopotamus is the animal that kills the most people in Africa. That's not to say she's not mostly vegetarian, but she's big strong with a huge mouth and aggressive.
According to my memory, a rhinoceros is also a vegetarian animal and despite this it is very dangerous because it is large and aggressive.
Drawing the decisive conclusions from the finding of the fossil is out of place. To conclude something so fundamental about the behavior of an entire species based on a one-time event by a specific Tyrannosaurus is going too far, to say the least.
This can be illustrated using the hippopotamus for example. It is a vegetarian mammal whose stomach is not adapted to eating meat. At the same time, rare events of predation, eating carrion and even cannibalization are known. See: http://he.wikipedia.org/wiki/%D7%94%D7%99%D7%A4%D7%95%D7%A4%D7%95%D7%98%D7%9D
I remember that I once saw a rare photograph in National Geographic where a hippopotamus is seen eating an antelope. Unfortunately I couldn't find any documentation for this online. In any case, assuming that the hippopotamus will become extinct one day and a future paleontologist will find an antelope bone with a piece of hippopotamus tusk, he may reach the wrong conclusion reached by the researchers mentioned in the article. Sometimes we have to admit that we don't know and probably won't know either.
To Shimi - beyond what Yotam told you, I will add and say that the attitude you express is very utilitarian. Sometimes things have value in themselves, regardless of the results they produce. In my eyes, evidence that examines things only according to their potential to bring us one benefit or another is superficial and one-dimensional, and misses much of the richness (and happiness) of human existence. Simply put - we care because it's interesting, and it really doesn't matter what science makes of it later.
You could also say that about Newton.
Newton was looking for legality for the movement of the heavenly bodies, like many before him. How exactly could finding such legality help humanity in the 17th century?
I'm sure you know how much Newtonian mechanics contributed to humanity in retrospect.
Science tries to understand and give legitimacy to the world, it is not always clear what the application will be. The more puzzle pieces you have, the better you can understand the overall picture. You won't be able to tell which piece of the puzzle is important and which isn't until you start putting them together.
A very serious question
who cares? What does it matter if an animal that existed a few thousand or millions of years ago was a vegetarian or a ferocious carnivore? What can science learn from this that will help us later?