Megalodon vs. Livyatan melvillei

[theropod]

Who is talking about "vice versa"? Obviously adult male killer whales are less agile than females or subadults, there’s nothing special about that (I just don’t see why that’s important, was it ever up to debate?). The thing I was pointing out was just that they can and do participate in hunting at least occasionally. Certainly male lions are also less agile and efficient hunters than the females, but demonstrably that does not mean that a male lion in itself is an animal with unusually poor agility for its size, or incapable of hunting if it has to.

So if you’re not suggesting there there’s something about the orca’s body plan in particular that causes it to becoming less agile at larger sizes any more so than other marine animals, what’s the relevance of this whole thing? Hasn’t it already been pointed out and generally agreed upon years ago, that larger animals are less agile than smaller animals.

[elosha11]

^As to "vice-versa" I thought the article you posted might be construed to suggest that. I was simply pointing out the bulk of observations shows males less involved in attacks overall than females, and it's postulated that its slower speed/agility helps explain this.

The "relevance" is that you and I aren't the only ones reading and posting on this thread and some points bear repeating. It's not at all intuitive or well known to many that male orcas might be a bit less agile than females, and since it's sometimes proposed that Livyatan was an orca shaped predator, we simply need to make the record clear, along with the further implications for larger body size. Same with Megalodon of course, we should expect less agility than a great white in turning radius. I do think probably both animals were capable of fast swimming, perhaps comparable or even exceeding GWS and orcas/FKW's (for somewhat short distance) but - as we all agree - turning radius for both giants would be curtailed in comparison. Of course when fighting each other in our hypothetical scenario or when attacking relatively large cetacean prey, this is less of a factor.

[Infinity Blade]

So, how are we all feeling about this match? Sam I’m guessing you favor the odontocete? Theropod, 50/50? What about you elosha?

[Grey]

I presently favor the shark simply because it grows noticeably larger according to the available modern data and it probably has a larger bite. Those are the decisive points to me.

[sam1]

If their sizes were similar, I easily favor the whale for numerous reasons (superior mobility and ramming which renders the bite far less important than what people usually perceive.. even still, the ultimate gripping bite evolved by livyatan is just as, if not even more devastating than a slicing bite. If someone needs clarification about this, let me know), although I believe the two only very rarely engaged in head on fights to the death.

[sam1]

Jul 26, 2018 5:00:07 GMT 5 elosha11 said:

Therpod, I'll respond to the above later today hopefully. But I just wanted to post these pictures of an estimated 3.5 meter tiger shark's attack on a bottlenose dolphin. We can clearly see that the first and incapacitating bite was a massive one just in front of the dorsal fin, followed up by second bite to the tail region. This is just one case, but it does demonstrate pretty graphically that sharks will attack the top dorsal side of a cetacean as the initial bite/attack.





Note that in the pictures above, the dolphin is only bit once on the dorsal side. The shark then follows up with another bite above the tail region.







From the article:

At first the pod of dolphins looked like any other but closer inspection revealed a straggler with a terrible bite out of its back and a shark in close pursuit. The dolphins initially circled their injured mate but as the shark moved in and the injured animal grew weaker they scattered.

After a few slow, wide circles the shark lunged, tearing another chunk of flesh from just above the dolphin’s tail.

That shark is clearly bigger than the dolphin.
That is what allowed it to secure such a devastating initial bite in the first place.

[sam1]

Jul 26, 2018 20:20:30 GMT 5 theropod said:

Whale sharks are not a good analogue for megalodon though, we don’t know what an actively predatory shark that size might have moved like, only that it was certainly less agile than a great white just like Livyatan would have been less agile than an orca.
This is were comparing raptorial odontocetes and at least somewhat similar-sized raptorial sharks would potentially be useful, probably more useful than some entirely speculative extrapolation of one but not the other to giant size.

I think whale sharks certainly have a fair deal of merit in this regard.
We shouldn't put lifestyle above the morphology in terms of importance here.
For example, many ballen whales aren't slower than similarly sized(sperm whale included) toothed macro predatory whales. 

On the other hand, one of the slowest shark species is not a filter feeder and is actually an apex macro predator, much smaller than a whale shark.

What we can compare for sure is the build plan. Filter feeder sharks have a pretty streamlined yet muscular bodies and large pectoral fins.
Megalodon was proportionaly a lot bulkier and much more massive animal, yet the automatic general conclusion still steers toward "oh but it was a macro predator so it must've been faster, let's just ignore the physics"

[Grey]

I'm still skeptical about the alleged superior mobility of a cetacean and the ability to stop moving appears to be good for defense but not ultimately decide the outcome.
Adult sperm whales don't impress me from this standpoind and I definitely doubt an adult meg would be at disadvantage against any Physeter.
I recall there are, here again, circumstancial evidence of the shark preying on large sperm whales (Purdy 1996).

The bottlenose dolphin is powerful, as large and larger than most bull sharks. Faster, more mobile and a far superior rammer, if this is what decides the winner in case of clash.

Yet the bull shark is its natural predator. US Navy experiments have showed bottlenose dolphins simply refuse to approach bull sharks.

Except for the absence of powerful bite, it looks like a close comparison with Livyatan and meg, in which case the whale is not larger than the shark.

I wouldn't state anything about Livyatan bite deadliness.

But it appears the size of the dentition of Bertucci meg jaws recreation is accurate (compared to associated sets). Despite the unatural position of the recreation, this dentition outsize Livyatan's bite volume by a wide margin. So I give the shark the edge too here.

Unless future data upsizes the physeteroid or downsize the otodontid, this is my statement.

[sam1]

So now you're moving down from FKW and GWS to bottlenose dolphins vs bull shark to support your argument and still missing many of my points stated before.
Ramming at 200kg vs ramming at 50000kg at the same speed? Seriously? Watch that slow motion of a whale shark colliding with a manta at very, very slow speed and see how its head reacted to the force.
Can you even begin to coompare that to a 40t sperm whale moving at ~30km/h?
Simply, a bottlenose dolphin doesn't have the tools to damage the bull shark seriously enough..its ram is not potent enough, and its jaws can't act as a secondary and finishing tool(like in my description of Livyatan and megalodon battle)

[theropod]

sam1: I’m not putting lifestyle above morphology, although obviously lifestyle and morphology are inextricably linked. It’s not as if Megalodon was likely to have looked anything like a whale shark. Whale shark morphology is simply quite different from Megalodon’s probable morphology, and simply put, whale sharks don’t seem to have any need for speed or agility, whereas C. megalodon certainly did.

Since we don’t see such major differences in speed between similar-sized, morphologically appropriate AND ecologically similar sharks and odontocetes, I fail to see why the fact that whale sharks are sluggish is evidence that the morphologically, ecologically and phylogenetically rather distant C. megalodon was too.

Baleen whales are also filter-feeders, but that’s were the similarity ends. I’m not saying that all filter-feeders are slow (in fact, that does not seem to hold true for basking sharks either), but even among filter-feeders, there are varying feeding strategies and. Rorquals are lunge-feeders that have to propel themselves through swarms of prey with opened mouths, taking in up to their own body mass in water. Whale sharks either ram- or suction feed. Obviously the former ecology requires different locomotory abilities than the latter. In addition, rorquals seem to be faced with far greater predation pressure than whale sharks (or at least, I know no record of orca predation on the latter, maybe because.

With the bulk of large whale sharks considered, C. megalodon was not necessarily that much bulkier (probably somewhat, but not massively). But a whale shark is simply not adapted for the same locomotory needs faced by a large macropredator, whose morphology was likely closer to other lamniforms, and even if for some reason it were, it would still be spending most of its time crusing slowly while feeding, because it simply has no reason to move quickly.
Again, great white sharks are not slow animals compared to orcas or Pseudorca. Can you demonstrate some inherent reason why sharks would suffer dramatically decreased mobility at larger sizes, much more so than whales?

Infinity Blade: With only one individual of Livyatan we can not scientifically conclude which taxon grew larger, but the one we have is without a doubt in the size range of good-sized to large adult C. megalodon, even at the lower end of plausible sizes. Assuming similar sizes, they are very evenly matched overall, albeit with very different strengths and weaknesses. The whale lacks the formidable cutting dentition and large gape, whereas the shark is inferior in ramming ability, ability to grip and manipulate its opponent with the jaws and has some shortcomings in mobility imposed by its respiratory system and tonic immobility (e.g. stopping, reversing, rolling and such). And the extant analogy suggesting either side to dominate in a similar-sized engagement simply does not exist, with the only cetaceans sharks take that are as large as, or larger than themselves being mysticete calves and small delphinids.

elosha11: Yes, but this has already been repeated over and over again. Literally every time agility is discussed, this comes up, as if it had any bearing on how Livyatan and megalodon compared in this regard. Since it changes nothing about this scenario, repeating it over and over again gives the incorrect impression that it did. Which I think is in fact a thing that can easily be misconstrued because the logical assumption if something gets posted repeatedly is that those who post it want to actually make a point with it.
The only thing the quote from Pitman et al. can be construed to suggest is that the role of the adult male orca in prey capture is a variable one. It does not disagree with the notion that adult males are less agile than females or subadults, not does it suggest the opposite. I did think that it was important to remind that the male is quite capable of hunting though, especially since the reduced agility and hunting efficiency of the males is being highlighted this much.

[elosha11]

Jul 28, 2018 14:20:55 GMT 5 sam1 said:

Jul 26, 2018 5:00:07 GMT 5 elosha11 said:

Therpod, I'll respond to the above later today hopefully. But I just wanted to post these pictures of an estimated 3.5 meter tiger shark's attack on a bottlenose dolphin. We can clearly see that the first and incapacitating bite was a massive one just in front of the dorsal fin, followed up by second bite to the tail region. This is just one case, but it does demonstrate pretty graphically that sharks will attack the top dorsal side of a cetacean as the initial bite/attack.





Note that in the pictures above, the dolphin is only bit once on the dorsal side. The shark then follows up with another bite above the tail region.







From the article:

That shark is clearly bigger than the dolphin.
That is what allowed it to secure such a devastating initial bite in the first place.

But that wasn't at all my point in posting it. No question the shark is bigger. However, it had been suggested earlier (I think by both you and possibly Theropod) that sharks don't often attack the dorsal side first and that cetacean prey use this almost as a defensive mechanism to ward off a more harmful bite to the belly. I was posting this to demonstrate that sharks can, in fact, assert a crippling bite to the dorsal area as their initial attack. BTW, this tiger shark wasn't giant, it was only estimated at 3.5 meters long, which is big but certainly not close to extraordinary. It's not dwarfing the dolphin by any means.

If what you are suggesting is that sharks can only attack and kill dolphins on the dorsal side when there's a large size difference between the two, I think there's way too little data on these specific types of attacks to say one way or the other. However, I am going to track down the study I mentioned earlier, which I think will shed some light on this.

Lots of interesting posts; I'll try to comment in much more detail later this weekend.

[elosha11]

More evidence that great whites attack dorsal areas of dolphins quite frequently. This involves a 3.5 meter dolphin in the Mediterranean attacked on its dorsal side by a white shark exceeding 4 meters. I have to print screen images, as I can't get the article to copy properly. Here's the website article. Note that even though the dorsal region is noted as a more challenging spot for the shark to bite, it is still a common enough attack point, which again suggest the bite marks posted the dorsal areas of false killer whales are more likely to be interpreted as predatory attempts by a large shark. The bites may have been a from a white shark or tiger shark (most likely candidates) but could have also been a very large bull or mako shark.

www.dlib.si/stream/URN:NBN:SI:DOC-QGL0JFDV/ae0c52fd-8d43-4c16-b2d2-3491452ac0c7/PDF

Attachments:

[sam1]

I thought it is obvious that they aren't deliberately attacked on the dorsal area. I mean, sharks don't attack their prey from above, especially not to bite the least vulnerable area!

What happens is that when shark attacks and dolphins see it in the last moment, they roll to expose the back instead of the belly or side area that was initially targeted by the shark.

And yes, my point is that it takes a big size advantage for a shark to fatally wound a dolphin this way.
At parity, no way. The bite is just too small.

[theropod]

elosha11: In their discussion of white shark attack patterns, Long & Jones 1996 wrote pretty much exactly what Sam has suggested; that the dorsum is far less vulnerable, as demonstrated by the greater number of healed bite wounds in this area.
Added to that, an attack from above, as would be required to strike the dorsal surface, is also less likely than a ventral approach. So I think it’s save to say that the dorsal surface is not especially targeted in predatory attacks (and the numbers support that, 68% of bites documented by Long and Jones were in the caudal peduncle).
That doesn’t mean that a powerful shark can not cause crippling injuries by biting a cetacean in the back, just that it is less likely to do so than in other parts of the body and would thus probably try to target those regions that will most likely result in success. And the sharks that left the bite marks on Pseudorca individuals were obviously unable to cause fatal damage, otherwise the purported prey wouldn’t have survived.

Ergo, a dorsal bite wound can not automatically be assumed to stem from a predatory attack on the basis of bite placement, while this could probably be relatively safely assumed for a bite wound in one of the areas specifically targeted in predatory attacks.

A whale that unsuccessfully preyed on a shark and got bitten in the process might also sustain such a bite wound, especially if it was from a moderately sized shark (since predation on a relatively small prey item is more likely). Sucker marks on sperm whales aren’t proof the squid tried to prey on the sperm whale after all.

[Grey]

Jul 28, 2018 15:43:45 GMT 5 sam1 said:

So now you're moving down from FKW and GWS to bottlenose dolphins vs bull shark to support your argument and still missing many of my points stated before.
Ramming at 200kg vs ramming at 50000kg at the same speed? Seriously? Watch that slow motion of a whale shark colliding with a manta at very, very slow speed and see how its head reacted to the force.
Can you even begin to coompare that to a 40t sperm whale moving at ~30km/h?
Simply, a bottlenose dolphin doesn't have the tools to damage the bull shark seriously enough..its ram is not potent enough, and its jaws can't act as a secondary and finishing tool(like in my description of Livyatan and megalodon battle)

Why do you need to be agressive ? Are my posts agressive ? No.

The difference of scales doesn't matter. The fact is the dolphin, which is larger on average than a large bull shark, a better rammer and more mobile...still falls prey to this shark. Yes the dolphin doesn't have the massive bite but this comparison was compensated by the massive size advantage of the dolphin.

The fact is no odontocete is known to have killed a macrophagous shark the same size individually and usually the cetacean is the one avoiding the fish.

Definitely, knowing the ecological interactions between FKW and GWS would certainly be a better source of comparison, although as theropod said, the dolphin here appears to be a bit smaller-jawed for its size compared to Livyatan.

There is no doubt though, despite their formidable dentition, that I favor any GWS like Apache or Deep Blue against any FKW.

There are strong hints, based on some gigantic teeth from various positions, that C. megalodon may reach and perhaps exceeded 20 m long.

That is not the case for Livyatan, neither the holotype nor any isolated teeth specimen found elsewhere in the world suggest something larger than the upper estimate of 17.5 m so far.

Based on this, megalodon appears to be the species with the most powerful individuals.

Again, I'm perfectly open to revise this depending on future discoveries and datas.

At parity size, it is a toss up.

One thing about Livyatan's alleged mobility, knowing the shape of its pectoral would also certainly help.

Interestingly, a scientific journal wrote about this match :


issuu.com/synapsebristol/docs/synapse_issue_9_nobleed_2