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For this question, I've got a pretty large carnivore. I haven't quite decided on their hunting style, but am leaning toward them being an endurance hunter. They're comparable in size to a large present-day Earth feline (lion, tiger or similar) and have long, rather sharp claws useful for grasping, holding and cutting.

There are two traits that I'd like to have in this species, which I am trying to figure out if they could evolve together.

One is long canine teeth. Not quite the size of those of a Smilodon (also), but certainly in line with those of Machaeroides eothen or perhaps slightly longer:


(Image source)

The other trait I'm looking to have is that they kill, at least at times (as in, not necessarily every kill is done this way, but a non-negligible fraction of kills are), by actually crushing or biting through the skull of their prey.

Jaguars come pretty close to fitting the bill for the latter, but their canines are comparatively shorter.


(Image source)

Can I plausibly have both, or will I have to settle for one or the other? Particularly if the latter, then why?

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  • $\begingroup$ @RonJohn I appreciate your attempt at improving the title of my question, but I'm not asking if a carnivore does kill by this method; I'm asking if I can have both of these traits in the same creature. $\endgroup$ – a CVn Mar 13 '18 at 23:22
  • $\begingroup$ Sorry, I meant to write "Can". $\endgroup$ – RonJohn Mar 13 '18 at 23:32
  • $\begingroup$ I can't think of any animal that crushes its prey's skull to kill it. Canines are for poking holes in flesh, grabbing things, and severing vertebrae. $\endgroup$ – Mazura Mar 15 '18 at 5:54
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I don't think so, since the "saber teeth" are so long that they extend far out of the mouth that they'd get in the way of trying to crunch down on it's prey's skull. (Imagine trying to bite into an apple if you had such long teeth.)

To crush something large with your jaws, you need:

  1. a large enough jaw,
  2. a wide jaw,
  3. a strong temporalis muscle (to pull the lower jaw up),
  4. a large coronoid process (anchors the temporalis to the lower jaw),
  5. a large temporal bone to anchor the temporalis to the skull, and
  6. nothing impeding access to the mouth.

The jaguar's skull meets all six of those criteria, and that's what any carnivore needs. To me, it looks like the Machaeroides eothen teeth would fail criterion 6.

enter image description here

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    $\begingroup$ In reality, the teeth of Smilodon were more for show; it actually made them every inefficient eaters (they couldn't reach most inner parts of a carcass) and even their killing techniques required them to fatigue their prey first so as not to risk damaging their canine teeth when they struck the death blow. The teeth were probably more for presentation effect than anything else, but given that they were present in both genders, we don't know for sure. $\endgroup$ – Tim B II Mar 14 '18 at 0:12
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    $\begingroup$ "they'd get in the way of trying to crunch down on it's prey's skull" I'm not so sure that'd necessarily be the case. Some species of snake, while admittedly not directly comparable, have the ability to open their jaws far beyond what one might be used to in mammals. Also note that I'm specifically asking about teeth not as long as those of a Smilodon. $\endgroup$ – a CVn Mar 14 '18 at 8:10
  • $\begingroup$ @MichaelKjörling the Smilidon's lower jaw is pretty anemic. No crushing there!! :) See my edited answer, for more. $\endgroup$ – RonJohn Mar 14 '18 at 8:17
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    $\begingroup$ The problem with "just open wider" is that at some angle the forces involved stop making sense. But you could handwave this away. $\endgroup$ – Borgh Mar 14 '18 at 14:29
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    $\begingroup$ @GarretGang were the skulls crushed, or were they pierced? Smilidon had a weak jaw, but a strong neck. That would allow Smilidon to drive it's two teeth down into it's prey like daggers. $\endgroup$ – RonJohn Mar 15 '18 at 23:36
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You have to consider how such a creature might have evolved.

If it has long canines and is adapted to crushing, then maybe it uses mostly the canines to kill, and then the crushing force to break some prey's hard skull. Brains are rich in omega-3... As far as I know, the next best source is the liver of deep-dwelling fish, which except in salmon-rich areas would be too rare for a land-dwelling animal.

Maybe your hunter feeds on thick-skulled goats?

Last but not least, there is precedent in our world for long, pointy teeth and great crushing force on tetrapods. Crocodiles sometimes eat turtles, and they use their great bite strength to break through the shell. Now look at the teeth of a saltwater crocodile:

See you in a while, crocodile

If your hunter is a mammal, it might be one that is evolving to fill in a niche which belonged, or would have belonged to crocs.

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  • $\begingroup$ Crocodile teeth are -- comparatively -- nowhere near as long as Machaeroides eothen canines. $\endgroup$ – RonJohn Mar 14 '18 at 8:46
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It could but usually not because there are easier methods of dispatching prey.

A skull is usually thick and strong to protect the brain while the neck is soft and full of arteries and the windpipe.

Why attack the enemy at their strongest point when you can attack the weakest?

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    $\begingroup$ "Why attack the enemy at their strongest point when you can attack the weakest?" Ask the jaguar :-) $\endgroup$ – a CVn Mar 14 '18 at 8:11
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    $\begingroup$ yup, jaguars do this a lot. The problem with weak points is that creatures will try to protect it, jaguars got around this problem by just not giving a fork. $\endgroup$ – Borgh Mar 14 '18 at 14:26
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There is a real-life animal that crushes skulls with its mouth, but as means of self-defence against predators: the hippopotamus. If you want examples, just look up "hippo crushing lion head". Hippopotamuses also have large, pointed canines in their mouths.

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The long canine teeth of Sabre Tooth tigers and their relatives were evolved not for crushing, but for stabbing, particularly stabbing through the neck of their prey and slicing through blood vessels, cutting nerves and otherwise incapacitating their prey.

Lions, Tigers and other large cats attack the necks of their prey, trying to crush the windpipe, cut through blood vessels, break the neck or strangle the prey, and Sabre Tooths just ramped that up because their prey were ice age megafauna:

enter image description here

Bite though this....

Crushing skulls, while it sounds exciting, is pretty difficult. The skull is one of the strongest parts of the body by design, since it shelters the brain and many of the sense organs, and is also generally large, requiring a pretty big mouth in relation to the skull just to fit in enough to get a good bite.

enter image description here

You need jaws about this size to do the job....

Crushing is also something which requires flat surfaces, look at the jaws of a nutcracker compared to a steak knife. In the animal kingdom, crushing is done by molars. This is actually so energy intensive, many animals outside of mammals simply bite off the leafs etc and send it to a "crop" where it is ground up by the action of rocks that the animal swallowed. This isn't a very viable plan for a predator.

The only creature which can reliably crush skulls are human beings. The Ancestors learned long ago to amplify the power of their arms with rocks and clubs made of bone or wood. This should give you some idea of the leverage involved, and the potential size of the jaws that a "skull crusher" would need.

enter image description here

This much leverage....got it

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