7 ms·

Fossil shows mammal sinking teeth into dinosaur

102 points by Hooke 3y ago

pleb_nz 3y ago
Pretty sure it would have gone both (all) ways where the opportunity arose just as it does between today's animals. I doubt people truely think that only dinosaurs were top predators across all sizes, groups and timeframes.
rvba 3y ago
When a cat captures a bird, isnt that a situation where a mammal sinks teeth into a dinosaur?
- Tagbert 3y ago
  Or… https://coronadovisitorcenter.com/wp-content/uploads/2014/10/KentuckyFriedChicken_Coronado.jpg https://coronadovisitorcenter.com/wp-content/uploads/2014/10...
ecf 3y ago
In my opinion, it’s more likely that the mammal climbed the carcass to access meat that larger mammals already consumed from the ground level. Zero chance something this small is actively trying to take down prey as large as this.
- datameta 3y ago
  It states in the article that there are zero bite marks on the fossil, so it could not have been attacked prior.
massifist 3y ago
Is there a reason why they don't suggest the possibility that this was a mammal scavenging the carcass of a dinosaur? And would this be a surprise, other than providing an interesting specimen?
- riccardomc 3y ago
  Yes, there is a reason: “The lack of bite marks on the dinosaur skeleton, the position of the mammal atop the dinosaur, and the grasping and biting actions of the mammal, collectively signal that the mammal was preying on the weakened dinosaur when the two were suddenly entombed by a volcanic debris flow,”
karim79 3y ago
> Experts revealed the 125m-year-old fossil that froze in time after being taken on by a small mammal a third of its size. They are tangled together, the mammal’s teeth sunk into the beaked dinosaur’s ribs, its left paw clasping the beast’s lower jaw. I'm pretty sure my little dog would do something similar if she encountered a wild boar in the forest. I'm quite sure that if I were successfully chased down by a velociraptor, I would not just lay down and wait to be eaten. > Researchers said the discovery challenged a long-held view of early mammals as “fodder” for dinosaurs. I don't really get how that "challenges" any view at all. As if dinosaurs never got bitten nor scratched by stuff they were trying to eat. And with an erupting volcano nearby, I'd probably fight harder just for the hell of it and to mess with the palaeontologists.
- bitwize 3y ago
  Velociraptors were roughly turkey sized. I doubt one could eat a healthy human. The Jurassic Park "raptors" were badge-engineered Deinonychus. There's a smaller predator, larger prey phenomenon I find fascinating, and it has to do with how a modern dinosaur -- the peregrine falcon -- takes its prey. It literally falcon-punches its victim -- diving at high speed to strike with a closed talon. It can make a meal of a bird about twice its size this way, though usually it feeds on pigeons, other small birds, and the occasional small reptile or mammal.
  - ChrisMarshallNY 3y ago
    It’s always fun, watching small hawks and falcons, trying to fly off with their kills. It’s a series of “hops.” As for nasty small critters, look at pretty much anything in the mustelid (weasel) family. Pound for pound, the nastiest critters on Earth. Wolverines have been known to hunt caribou. And, of course, we have the honey badger: https://m.youtube.com/watch?v=4r7wHMg5Yjg https://m.youtube.com/watch?v=4r7wHMg5Yjg
  - Sparkyte 3y ago
    Their noodle necks would only be strong enough to draw blood and maybe slowly tear flesh. They looked to rely on their razor like teeth more than jaw strength. A human could beat them with kick. Anyone says they have a strong bite doesn't pay attention to other animals with similar jaws. Crocodiles for example can do 3700 PSI but is supported by a rigid neck and doesn't have to deal with the weight to support its jaws. This is also support by a jaw snapping mechanism. You could effectively hold a crocodiles mouth shut with no force at all. This would say the Jarasic Park ones had 1000 PSI, but real life ones 100 PSI and the teeth did all the work. Yeah I think humans have a stronger jaw, further the mouth extends from the jaw the more muscle it needs. Looked up a caiman bite force it about 400 PSI. There are some that can do more but it makes sense crocodile bite force is how much it can do with its weight. Slightly larger than a chicken Dino isn't going to compete with a caiman.
peter303 3y ago
I eat chicken regularly.
23B1 3y ago
But Brusatte said there remained some legitimate concerns about the integrity of the fossil. “There have been doctored fossils from this part of the world before, and the scientists did not dig up this specimen themselves. The skeletons are no doubt genuine, but I suppose the poses of the bones could have been altered, although I have no direct evidence for this,” he said. The downstream effects of a post-truth post-trust era.
- zgluck 3y ago
  "There have been doctored fossils from this part of the world before" - so, he obviously means "from China". This kind of etiquette is weird. (And of course I pretty immediately felt the voting feedback on why. So much pride in a dictatorship; that is also weird.)
  - maxbond 3y ago
    Maybe they meant that region of China. Or maybe they just liked that phrase. I think you're reading too much into this.
  - Etrnl_President 3y ago
    Best China > West China
- Kamq 3y ago
  > The downstream effects of a post-truth post-trust era. All this era has shown us, is that we should never have been relying on trust in anything even close to science. Trusting people to put the truth their own career advancement is how we got into this mess with the replication crisis.
  - wredue 3y ago
    [flagged]
    - edgyquant 3y ago
ricardobayes 3y ago
Looks like a mediahack to be honest
kijin 3y ago
Can we tell whether the mammal was actually trying to take down a dinosaur, or it was merely scavenging on a (nearly) dead dinosaur? Signs of resistance on either of them?
- ksherlock 3y ago
  The paper discusses that. https://www.nature.com/articles/s41598-023-37545-8 https://www.nature.com/articles/s41598-023-37545-8 It is possible that the mammal was scavenging the carcass of the dinosaur when the two became buried. This proposed scenario would account for the large size of the dinosaur relative to the mammal (terrestrial predators usually favour prey that are not much larger than themselves, particularly when hunting alone), and the fact that the mammal was biting the ribs of the dinosaur when it died, which would otherwise have been difficult to access (but not impossible—see below) on a living prey item. However, while plausible, we cite three lines of evidence that challenge this hypothesis. First, the bones of the dinosaur are otherwise devoid of tooth marks, which are commonly left by carnivorous mammals while scavenging. Second, it seems unlikely that the two animals would have become so entangled, were the dinosaur dead prior to the arrival of the mammal. Third, the scavenging scenario does not predict the position of the mammal atop the dinosaur, since the mammal could presumably just as easily have eaten the dinosaur from ground level. We propose instead that the two animals were buried in an act of predation on the part of the mammal, only for both to have been entombed by a sudden lahar-type volcanic debris flow (Fig. 2). This hypothesis would explain the entwined nature of the skeletons, wherein the left hindfoot of the mammal became trapped within the folded left leg of the dinosaur when it collapsed to the ground. It would also account for the lack of tooth marks and other indications of scavenging on the dinosaur’s skeleton, and for the mammal’s position atop the dinosaur, as though to subdue its weakened prey.
jameshart 3y ago
Seems dangerous to infer too much about the general behavior of entire species based on the observed behavior captured in two individuals at the moment they were being entombed in the lava flow from a volcanic eruption. Like assuming that based on some skeletons found under a volcanic ash flow that the normal behavior of humans was running with your hands in the air and screaming really loudly.
- Waterluvian 3y ago
  This drives me mad about these sciences. They seemingly get captured by the PR need to sell a digestible narrative. I appreciate if they want to posit ideas, but so often there’s this tone of absoluteness to them. I wonder if part of it is just the desire to make one’s discipline more exciting.
  - maxbond 3y ago
    You don't think that has more to do with science reporting?
    - inciampati 3y ago
      It is due to science reporting, which is in an eternal crisis. It can probably never catch up with the state of the arts.
- riccardomc 3y ago
  In this specific case the assumption is for the entire Mammalia class rather than just species
- Tao3300 3y ago
  It was a mud flow. It likely came on extremely fast while they were distracted by their life and death struggle, and not necessarily during a dramatic eruption. https://en.wikipedia.org/wiki/Lahar https://en.wikipedia.org/wiki/Lahar
  - 3y ago
therealdrag0 3y ago
You can watch videos of Jaguar going into the water and fishing out cayman. Why wouldn’t it be the same for dinosaurs? It’s only a matter of size and strength otherwise no taxonomy is magically safe from any other. Otoh with the mammal smaller like that it seems maybe like it could be more self defense or trying to distract a predator from their young or something other then the mammal being the predator..
firebirdn99 3y ago
Like a giant monster rat, or a badger actually - https://en.wikipedia.org/wiki/Repenomamus https://en.wikipedia.org/wiki/Repenomamus
causality0 3y ago
That fossil is too good. It's so complete and well-posed I'm almost certain it's at least been "reconstructed".

102 points by Hooke 3y ago

Pretty sure it would have gone both (all) ways where the opportunity arose just as it does between today's animals. I doubt people truely think that only dinosaurs were top predators across all sizes, groups and timeframes.

rvba 3y ago

When a cat captures a bird, isnt that a situation where a mammal sinks teeth into a dinosaur?

Tagbert 3y ago
Or… https://coronadovisitorcenter.com/wp-content/uploads/2014/10/KentuckyFriedChicken_Coronado.jpg https://coronadovisitorcenter.com/wp-content/uploads/2014/10...

ecf 3y ago

In my opinion, it’s more likely that the mammal climbed the carcass to access meat that larger mammals already consumed from the ground level. Zero chance something this small is actively trying to take down prey as large as this.

datameta 3y ago
It states in the article that there are zero bite marks on the fossil, so it could not have been attacked prior.

massifist 3y ago

Is there a reason why they don't suggest the possibility that this was a mammal scavenging the carcass of a dinosaur? And would this be a surprise, other than providing an interesting specimen?

riccardomc 3y ago
Yes, there is a reason: “The lack of bite marks on the dinosaur skeleton, the position of the mammal atop the dinosaur, and the grasping and biting actions of the mammal, collectively signal that the mammal was preying on the weakened dinosaur when the two were suddenly entombed by a volcanic debris flow,”

karim79 3y ago

> Experts revealed the 125m-year-old fossil that froze in time after being taken on by a small mammal a third of its size. They are tangled together, the mammal’s teeth sunk into the beaked dinosaur’s ribs, its left paw clasping the beast’s lower jaw. I'm pretty sure my little dog would do something similar if she encountered a wild boar in the forest. I'm quite sure that if I were successfully chased down by a velociraptor, I would not just lay down and wait to be eaten. > Researchers said the discovery challenged a long-held view of early mammals as “fodder” for dinosaurs. I don't really get how that "challenges" any view at all. As if dinosaurs never got bitten nor scratched by stuff they were trying to eat. And with an erupting volcano nearby, I'd probably fight harder just for the hell of it and to mess with the palaeontologists.

bitwize 3y ago
Velociraptors were roughly turkey sized. I doubt one could eat a healthy human. The Jurassic Park "raptors" were badge-engineered Deinonychus. There's a smaller predator, larger prey phenomenon I find fascinating, and it has to do with how a modern dinosaur -- the peregrine falcon -- takes its prey. It literally falcon-punches its victim -- diving at high speed to strike with a closed talon. It can make a meal of a bird about twice its size this way, though usually it feeds on pigeons, other small birds, and the occasional small reptile or mammal.
- ChrisMarshallNY 3y ago
  It’s always fun, watching small hawks and falcons, trying to fly off with their kills. It’s a series of “hops.” As for nasty small critters, look at pretty much anything in the mustelid (weasel) family. Pound for pound, the nastiest critters on Earth. Wolverines have been known to hunt caribou. And, of course, we have the honey badger: https://m.youtube.com/watch?v=4r7wHMg5Yjg https://m.youtube.com/watch?v=4r7wHMg5Yjg
- Sparkyte 3y ago
  Their noodle necks would only be strong enough to draw blood and maybe slowly tear flesh. They looked to rely on their razor like teeth more than jaw strength. A human could beat them with kick. Anyone says they have a strong bite doesn't pay attention to other animals with similar jaws. Crocodiles for example can do 3700 PSI but is supported by a rigid neck and doesn't have to deal with the weight to support its jaws. This is also support by a jaw snapping mechanism. You could effectively hold a crocodiles mouth shut with no force at all. This would say the Jarasic Park ones had 1000 PSI, but real life ones 100 PSI and the teeth did all the work. Yeah I think humans have a stronger jaw, further the mouth extends from the jaw the more muscle it needs. Looked up a caiman bite force it about 400 PSI. There are some that can do more but it makes sense crocodile bite force is how much it can do with its weight. Slightly larger than a chicken Dino isn't going to compete with a caiman.

peter303 3y ago

I eat chicken regularly.

23B1 3y ago

But Brusatte said there remained some legitimate concerns about the integrity of the fossil. “There have been doctored fossils from this part of the world before, and the scientists did not dig up this specimen themselves. The skeletons are no doubt genuine, but I suppose the poses of the bones could have been altered, although I have no direct evidence for this,” he said. The downstream effects of a post-truth post-trust era.

zgluck 3y ago
"There have been doctored fossils from this part of the world before" - so, he obviously means "from China". This kind of etiquette is weird. (And of course I pretty immediately felt the voting feedback on why. So much pride in a dictatorship; that is also weird.)
- maxbond 3y ago
  Maybe they meant that region of China. Or maybe they just liked that phrase. I think you're reading too much into this.
- Etrnl_President 3y ago
  Best China > West China
Kamq 3y ago
> The downstream effects of a post-truth post-trust era. All this era has shown us, is that we should never have been relying on trust in anything even close to science. Trusting people to put the truth their own career advancement is how we got into this mess with the replication crisis.
- wredue 3y ago
  [flagged]
  - edgyquant 3y ago

ricardobayes 3y ago

Looks like a mediahack to be honest

kijin 3y ago

Can we tell whether the mammal was actually trying to take down a dinosaur, or it was merely scavenging on a (nearly) dead dinosaur? Signs of resistance on either of them?

ksherlock 3y ago
The paper discusses that. https://www.nature.com/articles/s41598-023-37545-8 https://www.nature.com/articles/s41598-023-37545-8 It is possible that the mammal was scavenging the carcass of the dinosaur when the two became buried. This proposed scenario would account for the large size of the dinosaur relative to the mammal (terrestrial predators usually favour prey that are not much larger than themselves, particularly when hunting alone), and the fact that the mammal was biting the ribs of the dinosaur when it died, which would otherwise have been difficult to access (but not impossible—see below) on a living prey item. However, while plausible, we cite three lines of evidence that challenge this hypothesis. First, the bones of the dinosaur are otherwise devoid of tooth marks, which are commonly left by carnivorous mammals while scavenging. Second, it seems unlikely that the two animals would have become so entangled, were the dinosaur dead prior to the arrival of the mammal. Third, the scavenging scenario does not predict the position of the mammal atop the dinosaur, since the mammal could presumably just as easily have eaten the dinosaur from ground level. We propose instead that the two animals were buried in an act of predation on the part of the mammal, only for both to have been entombed by a sudden lahar-type volcanic debris flow (Fig. 2). This hypothesis would explain the entwined nature of the skeletons, wherein the left hindfoot of the mammal became trapped within the folded left leg of the dinosaur when it collapsed to the ground. It would also account for the lack of tooth marks and other indications of scavenging on the dinosaur’s skeleton, and for the mammal’s position atop the dinosaur, as though to subdue its weakened prey.

jameshart 3y ago

Seems dangerous to infer too much about the general behavior of entire species based on the observed behavior captured in two individuals at the moment they were being entombed in the lava flow from a volcanic eruption. Like assuming that based on some skeletons found under a volcanic ash flow that the normal behavior of humans was running with your hands in the air and screaming really loudly.

Waterluvian 3y ago
This drives me mad about these sciences. They seemingly get captured by the PR need to sell a digestible narrative. I appreciate if they want to posit ideas, but so often there’s this tone of absoluteness to them. I wonder if part of it is just the desire to make one’s discipline more exciting.
- maxbond 3y ago
  You don't think that has more to do with science reporting?
  - inciampati 3y ago
    It is due to science reporting, which is in an eternal crisis. It can probably never catch up with the state of the arts.
riccardomc 3y ago
In this specific case the assumption is for the entire Mammalia class rather than just species
Tao3300 3y ago
It was a mud flow. It likely came on extremely fast while they were distracted by their life and death struggle, and not necessarily during a dramatic eruption. https://en.wikipedia.org/wiki/Lahar https://en.wikipedia.org/wiki/Lahar
- 3y ago

therealdrag0 3y ago

You can watch videos of Jaguar going into the water and fishing out cayman. Why wouldn’t it be the same for dinosaurs? It’s only a matter of size and strength otherwise no taxonomy is magically safe from any other. Otoh with the mammal smaller like that it seems maybe like it could be more self defense or trying to distract a predator from their young or something other then the mammal being the predator..

firebirdn99 3y ago

Like a giant monster rat, or a badger actually - https://en.wikipedia.org/wiki/Repenomamus https://en.wikipedia.org/wiki/Repenomamus

causality0 3y ago

That fossil is too good. It's so complete and well-posed I'm almost certain it's at least been "reconstructed".