Megalodon vs. Livyatan melvillei

[theropod]

^I don’t doubt that at all, not too long ago I posted a video of a tiger shark contributing to the death of a blue whale.
Odontocetes can also kill prey larger than themselves, especially when hunting cooperatively, that in itself is not what’s up to debate here. The question is whether purported interactions between white sharks and false killer whales are really a good "proxy" for this fight, as has been suggested before.

Specifically, it has been claimed on here repeatedly that the comparison between FKW and GWS is more interesting for this scenario than that between Orcinus and GWS, due to the size difference between the latter two.
BUT:

• The size difference between great whites and their largest recorded odontocete prey is actually similar to that between orcas and the great whites they prey on, so with literally no evidence to the contrary, we should not assume that they make an exception for FKW of all animals
• The evidence that GWS even attack false killer whales at all is very weak, most of the argument having focused on a single account of a beached female with shark bite wounds which weren’t even necessarily very serious
• Livyatan is much more formidable for its size than Pseudorca, having a skull that is 50% larger at body length parity

So I don’t think that’s actually the case.

[elosha11]

Jul 25, 2018 18:17:34 GMT 5 theropod said:

There’s no single record of a GWS killing a FKW either though.
The only thing we have is a blog post reporting a damaged fin and "superficial" shark bite marks on a beached 3.8m female that later died in captivity. If this was failed predation by a great white shark (which is a possibility, but not the only one) then that hardly means it must have been a parity engagement, considering a 3.8m FKW would weigh around 400kg or less (based on data in Kasterlein et al. 2000). Cetaceans preyed upon by white sharks are consistently significantly smaller than the attacking shark, and the biggest scientifically recorded odontocete prey of C. carcharias are 3m beaked whales preyed upon by 5m great whites (Long & Lones 1996). So if great whites really do prey on the much more formidable false killer whale, then our default assumption should also be that they only do it with a considerable size advantage, just like orcas preying on great whites. The size difference between a 5m great white and a 3.8m FKW is not dissimilar to that between the 4.7-5.3m Orca and its 3-4m white shark prey observed by Pyle et al. (1999).

So while evidence that Carcharodon ever preys on Pseudorca is ambiguous to begin with, that’s still of far more limited use regarding size-parity interactions between macropredaceous odontocetes and lamniforms than has been suggested here, and certainly not evidence that sharks dominate these encounters at parity.

Furthermore, if Livyatan’s skull had been proportionally as small as Pseudorca’s, the holotype would have been 22-23m long and 65-90t (Baird et al. 1989, Pardo et al. 2009, Kasterlein et al. 2000). If we were to consider Livyatan comparable in morphology to Pseudorca, this would not be a parity matchup.
Pseudorca may reach lengths similar to great white sharks’, but a Livyatan the same length would be both far more massive and have much bigger jaws than a Pseudorca, and, unlike Pseudorca today, it was probably an apex predator mostly feeding on large mammalian prey, not mostly specialized on large pelagic fish and squid.

Baird, R. W., K. M. Langelier, and P. J. Stacey. 1989: First records of false killer whales, Pseudorca crassidens, in Canada. Canadian field-naturalist. Ottawa ON 103:368–371.
Kastelein, R. A., J. Mosterd, N. M. Schooneman, and P. R. Wiepkema. 2000: Food consumption, growth, body dimensions, and respiration rates of captive false killer whales (Pseudorca crassidens). Aquatic Mammals 26:33–44.
Long, D. J., and R. E. Jones. 1996: White shark predation and scavenging on cetaceans in the eastern North Pacific Ocean. Great white sharks: the biology of Carcharodon carcharias:293–307.
Pardo, M. A., C. Jiménez-Pinedo, and D. M. Palacios. 2009: The false killer whale (Pseudorca crassidens) in the southwestern Caribbean: first stranding record in Colombian waters. Latin American Journal of Aquatic Mammals 7:63–67.
Pyle, P., M. J. Schramm, C. Keiper, and S. D. Anderson. 1999: Predation on a white shark (Carcharodon carcharias) by a killer whale (Orcinus orca) and a possible case of competitive displacement. Marine Mammal Science 15:563–568.

Theropod, I know you just started actively posting again not too long ago, so you may have missed the below exchange re sharks v. FKW and what predictive value, if any, that may hold for Meg v. Livyatan. I see that you reference in the above post and the in subsequent ones that the primary evidence is the fearbelow.com article regarding 3.8 meter female with shark bites. Respectfully, however, there is quite a bit more evidence that that, as Sam1 and I discussed. See my quote below and you can also read our follow up discussions in June on this point.

Sam, since you correctly wondered why some arguments from the Meg average size thread re Meg v. Liyvtan weren't here, I thought I'd move over one part we discussed re great whites/other large sharks v. FKWs and whether that has any bearing on Meg v. Livyatan. For ease of reference, I'll quote my post on this and then your response from carnivora.



"I wanted to address your assertion in post 1833 as to why you would support both orcas and pseudorcas/false killer whales in a fight with a comparable sized GWS. The point you were trying to make is that this should be a reasonable proxy contest as to how Meg would interact with Livyatan. In summary you alleged that Livyatan, orcas, pseudorcas all share superior maneuverability, ramming ability and intelligence over their shark counterparts. Because of these presumed advantages you stated.

Now these are all the reasons why I would also favor any similarly sized orca or pseudorca against a gws in a head on fight..and in case of Livyatan they are only even more pronounced as it is even more suited for both ramming and gripping onto large opponents.

That pseudorca and pilot whales are avoiding the gws is just a normal and expected behaviour, all things considered.
It has little to do with their chances in the hypothetical equal term fight.
They aren't out there recklessly and mindlessly looking for tough and dangerous fights with great whites.

I will say that since orcas are so much larger than great whites, using those interactions is of little value to Meg v. Liyatan debate. I always thought the value we could gain in what is known between large sharks and pseudorcas would be somewhat useful as an analogy for Meg v Livy. For instance GWS and FKW are both formidable and comparable in size, unlike sharks v. orcas. They are much closer in size when comparing them directly to Meg and Livyatan.

Here's practically everything I can find about false killer whales v. sharks. I think the evidence suggests the animals interact infrequently and also suggests (note I did NOT say prove) that large sharks can be the aggressors in these interactions and have engaged in predatory attempts on adult false killer whales. They appear to bite the false killer whales around their dorsal fins, a common prey tactic for sharks preying on dolphins. Here's the evidence.

First, there is a recent video of a pod of false killer whales chasing down a small (probably 3-4 foot) reef shark and the lead fkw capturing and killing the shark. However, that shark was likely a juvenile reef shark and nothing like a GWS or other large shark (tiger, bull, mako). Here's the image and link. To the best of my knowledge, this is the only known aggressive/predatory behavior that false killer whales have exhibit toward sharks of any kind.

www.dailymail.co.uk/news/article-3582653/Pod-dolphins-hunt-juvenile-shark-Cronulla-pulling-deep.html (with video)




Now here's the evidence of large sharks' probable predation attempts on adult false killer whales.

Note that these bites could have been from other shark species, but given the size and formidable weaponry of false killer whales, great whites should be a prime suspect, along with tiger sharks.

Jul 27, 2014 9:51:13 GMT 5 elosha11 said:

Healed shark bite wounds on a false killer whale in Hawaii. From the website www.cascadiaresearch.org/hawaii/july2010.htm



The researcher states with reference to this picture: "False killer whale with recent shark bite wound and a long-term injury to the dorsal fin, August 5, 2010. Photo by Dan McSweeney. This individual is HIPc127 in our catalog, first documented off Maui in March 2000 (with the bent dorsal fin), and seen several times since both off Maui and the island of Hawai‘i. The shark bite wound behind the dorsal fin is the first time we've documented evidence of an attack by a large shark on a false killer whale in Hawai‘i. "

An interesting follow up to the above account re a shark bite on the dorsal side of a false killer whale in Hawaii. This below cited research article documents possible evidence of sharks biting false killer whales in the Caribbean.

"

Among the 71 false killer whales, 18 individuals (25.4%) showed a total of 20 injuries (66.7% dorsal fin, 27.8% body, 5.6% both dorsal fin and body) . .
. . Six individuals (22.2%) had an unidentified injury of which the cause is unknown. These include three individuals that appeared to have crescent-shaped scars on their body which were possibly inflicted by sharks. However, the photographs were of insufficient quality to confirm this. . . . Three false killer whales had injuries that may have been caused by sharks but other causes could not be ruled out. All wounds were located on the dorsal part of the dolphin, which is consistent with other studies [24], [25]. It has been suggested that odontocetes turn their back to the shark when they are attacked or that odontocetes with attacks on their dorsal side are more likely to survive the attack [25]. There are at least ten shark species which are known to predate on cetaceans [25] and six of these occur in the Caribbean, including tiger shark (Galeocerdo cuvier), bull shark (Carcharhinus leucas), sixgill shark (Hexanchus griseus), dusky shark (Carcharhinus obscurus), oceanic white-tipped shark (Carcharhinus longimanus) and mako shark (Isurus oxyrinchus) [63], [64]. It is not known which of these species occur in Aruban waters. In any case, these records indicate that local dolphins may be subject to shark predation.

Research article found at www.ncbi.nlm.nih.gov/pmc/articles/PMC3929637/

Finally, from www.fearbeneath.com/2009/12/shark-snacks-on-false-killer-whale/, shark attack in Austrialia.

A false killer whale that beached on the Sunshine Coast yesterday bore wounds thought to be from a shark attack, experts have said. The injured whale had a damaged dorsal fin and evidence of “superficial” shark bites.

The whale died after desperate efforts by up to 50 people who rushed to Twin Waters on a rescue mission. The 3.8 metre female was first spotted at 6:30AM south of Mudjimba Island.

Originally thought to be a pilot whale, it was later identified by an attending Australia Zoo rescue team as a “pseudorca crassidens” – a false killer whale.

And you responded to my post as follows:

elosha, hi, good to hear from you! And for your appreciation..makes all of this worth it. I appreciated your posts too, you are a shark advocate interested in constructive argument instead of "winning" a debate.
Of course I know about GWS predation attempts on FKW and Pilot whales.
I also know about one such account on adult Orca, that you didn't mention.
And frankly I don't see the issue. It's to be expected.
In fact I fully expect that meg sometimes preyed on Livyatan too, given the chance.

First, what is the account of a GWS predation attempt on an orca? I've heard rumors, I think from Grey, of a great white attacking a supposedly sick orca, but never seen any proof of it. Is that your account?

I think what you're doing is differentiating between possible shark predations on FKW's, etc. v. what you would see as a fight with both animals fully aware of the other. Frankly, I don't know how to distinguish because we have no idea if the FKW's in question in the accounts I posted were aware of the shark or not. For that matter, we don't know how the incident even turned out. All we know is that from the location of the bite marks, it seems likely to have been a predatory attack.

And keep in mind, the shark is inherently going to be going into a dangerous situation in attacking a FKW or a pilot whale because it will almost certainly be swimming close to its pod members. So ambush or not, the shark has every reason to try to make a quick kill before getting attacked by a pod of formidable and large predators. Don't know if we could ever get a fair "fight" under these circumstances, since the shark will always have to be alert to being attacked by other pod members, and the shark's natural inclination would be to attack quickly and with as much surprise as possible. Such an attack is in the shark's best interest. All we can say for certain is there is evidence that large sharks occasionally prey or at least attempt to prey on false killer whales, which are generally as large as the sharks. There's no evidence as of yet that indicates the shark would be disadvantaged in this conflict.

Based on this admittedly limited evidence, I don't really see how it could be used to support an argument for Livytan over Megalodon. Again, whether or not you want to argue that Livyatan would have a mobility/agility advantage over Megalodon just like FKW over great whites, such a possible advantage doesn't seem to stop large sharks from occasionally trying to prey on FKW's.

I do find the FKW v. great white to be interesting because it probably the closest modern analogy to Livytan v. Megalodon. Similar size and formidable weaponry for both. But still it's really hard to extrapolate too much from the interactions of these far smaller animals. Also, FKW are dolphins rather than whales, and there may be behavioral as well as morphological differences that would affect Livyatan differently than a dolphin. I really hope there will be more evidence of shark/FKW interactions in the future.

What I will say again, is that while the evidence is indeed limited, it does decidedly indicate that large sharks do at times attack and injure FKW in predatory encounters. There is no evidence yet that FKW attack large predatory sharks, despite their size, formidable natures, (they are thought to be just as, or perhaps even more aggressive than orcas), and the advantages of being in a pod.

This again is of limited evidentiary value, other than it further supports the rather well documented hypothesis that, when the prey is at parity size or below the shark's size (but still sizeable), large sharks seem to have a predatory advantage over sizeable cetaceans, such as dolphins and small whales. In other words, large sharks are more likely to kill (or at least attempt to kill and injure) the cetacean than vice-versa. While that hypothesis is cautious and tentative, and subject to change based on future evidence, it is currently well supported. Now such evidence can be used or not used when it comes to Meg v. Livyatan. I do not think it would provide more than a tenuous, but supportable point. But it is certainly a material factor in my mind.

[theropod]

OK, thanks. You are right, I had not read that post.
But is there any other confirmed case of a Pseudorca succumbing to, or at least in the aftermath of, a shark bite? If not, then how are we to be sure that the bite marks are the result of failed predation by sharks on Pseudorca, and not, for instance, the reverse?

Tying in with this, are there any orca bite scars on sharks? We do know the former prey on various sharks rather commonly, so if there are none (I for one have never seen any) then the absence of FKW bite marks (which would be hard to distinguish from orca bite marks at any rate) is not indicative of a lack of predation, just of shark skin not tending to preserve scars the same way cetacean skin does.

Also, how does this change the point I brought up about the size difference between a great white and its hypothetical FKW prey probably being comparable to that between orcas and great whites?

[elosha11]

Well, one piece of evidence that rather strongly suggest the shark was the attacker, rather than the victim, in these incidents is that every single one of the bite marks on the FKW in the above incidents happened around their dorsal fin region, which is the one of the most common places for great whites and other large sharks to attack and prey upon other cetaceans. It's quite common to see anywhere from large to superficial tooth wounds from a shark attack on a dolphin's dorsal region. Relatively minor wounds probably means the dolphin was able to slip away quickly before the shark could do too much damage. But sometimes the damage is severe, such as a removed dorsal fin, or huge blood wounds. Still the dolphins to get away sometimes. Perhaps their pods assists in some occasions, although usually a pod of dolphins will flee a large shark intent on predation, regardless of how greatly they outnumber it (note this is different than chasing a shark not in predatory mode).

So the bottom line is we're not sure how the interactions happened or played out, but the evidence clearly is indicative of the shark attacking the FKW. Given their size, formidable nature, weaponry, and pod-behavior, I think that qualifies as a pretty impressive attack by the shark.

As to the question of whether, we've seen a FKW killed by a shark, not to my current knowledge. But I believe the animals interact fairly infrequently, given the inherent risks to both. So it's a wonder we have any evidence of their interactions at all. That being said, everything I've seen so far suggests the shark is the animals seeking to predate on the FKW in these scenarios.

[theropod]

This is a common region to find bite marks on living cetaceans, but is it a common place to find bite marks on cetaceans that were actually killed? In all the pictures I can find of dolphin carcasses with shark bites, the bite marks are actually on the ventral side of the animal.

Sam suggested that cetaceans roll to present their dorsal surface to a bite as a protective measure, which makes sense and would explain the distribution of bite marks, but this would imply that this will only result if the cetacean is aware of the shark, i.e. not successfully ambushed from below. So it would not be a spot specifically targeted during a predatory attack, which means it is not exclusive evidence of predation either. With no clear evidence to determine the actual nature of these animals interaction, it’s pretty strange to consider it an important factor, don’t you think?

Note that I’m not saying that shark predation is less likely at all, but as I already wrote, that’s because if they do, the sharks doing so are probably a lot larger than the false killer whales they attack. Which brings with it the same problem as using killer whale vs great white as an analogy for this matchup, that the two animals involved are not the same size.

Added to the lack of any observed predatory interaction or confirmed kill, the fact that Livyatan was evidently much more well-armed than a false killer whale, and the difference between predation and a fight situation (think tigers killing rhinoceroses), could you explain why you think the purported predation of large sharks on false killer whales has more relevance here than the confirmed predation of killer whales on great whites?

I really don’t see any solid evidence at this point that sharks dominate encounters with same-sized macropredaceous odontocetes. Given that there are no documented encounters, that is not very surprising. I presume that by "rather well-documented", you are referring to predation on small-prey specialists such as bottlenose dolphins and other small taxa, but I don’t see how that’s relevant here. And even with smaller dolphins, predating sharks usually seem to have a size advantage (Long & Jones 1996).

[elosha11]

First, please note that a 3.8 meter FKW is probably an average size female FKW. It's certainly not small, and 3.8 meters would not be a small tiger shark, or for that matter even a small great white. There's no way to now guess how large the shark was that bit it, but 2.8 meters is either an adult female FKW or a large subadult. It certainly isn't a juvenile.

Also please note that the FKW with the bite mark from Hawaii in the picture I showed you, was identified as an adult over 10 years prior to the bite mark. I also note that particular animal seems to be quite bulky. It's noted as individual HIPc127 in both the picture and in the following 2005 research article, in which it was identified by the bent dorsal fin it still had in 2015. www.cascadiaresearch.org/oldsite/robin/BairdandGorgone2005.pdf. I cannot tell if it is male or female, but given how bulky it appears in the picture, my guess is it's probably a male. And a male that old is probably going to be 5 meters or longer. A female that old will likely be well over 4 meters. Almost undisputedly, a shark attacked a very large adult FKW in this 2015 picture and attacked a portion of the FKW often targeted in predatory interactions.

To my recollection, I believe sharks do commonly attack cetacean's dorsal area by ambush. While they may attack even more commonly from below on the ventral side of the dolphin, attacks from above and to the side also cancels out the dolphin's echolocation and is a common attack strategy. I believe there is a research article supporting this specific point for great white sharks, and I'll try to find it when I have time.

I never said this inquiry was an "important factor" to the Meg v. Livyatan hypo, if you are trying to imply that I think it's a dispositive factor. I do think it is somewhat material, although ultimately somewhat speculative and subject to change, like all hypotheses. I've been very cautious on how I apply this to the conflict between the far larger animals. Yet imperfect as it may be, this is by far the best analogy we have to the prehistoric conflict we are discussing. You state that Livyatan was much better armed compared to a FKW. Or course, it goes without saying that Megalodon was far better armed than a great white shark, with larger, overall more comparatively robust teeth, and apparently a more aggressive attacking style. But it's also true to state that FKW's are formidable biters. They can eviscerate gigantic tuna, they've been known to attack (flesh graze??? ) large whales, and I even read recently that on that one occasion where the orca rammed the female FKW out of the water and ate her calf that not only did the FKW adult swim away without apparent serious injury (granted there could have been significant internal damage that was not observable), but that the researchers also noted long rake marks on the attacking orca that they had not noticed before the attack. They surmised that it was possible that the FKW was defending itself vigorously and noted that orcas may not often attack FKW's given their size and ability to aggressively defend themselves. So let's not sell the FKW short here. They are without a doubt the second most formidable dolphin after the far larger orca. Any shark attacking the FKW would potentially have a serious fight on their hands, and yet apparently the sharks still do. That should tell us something with regard to how sharks and cetaceans interact now, and perhaps how they interacted in the distant past.

As to why I think shark's potential predation on FKW has more relevance than orcas v. great whites, I would think it's pretty obvious. GW's and FKW roughly overlap in size and weight and are really quite similar. I think sharks may be heavier on the top end of the scale but it's close. I think that's remarkably similar to what we see with Megalodon v. Livyatan, with the animals generally being in same size range. But great whites v orcas is a completely different size class? It's almost like a hippo v. an elephant. Both enormous animals, but when you see them fight, you see just how much larger the elephant is than the hippo and how that enormous size advantage influences the fight.

Lastly, as I've stated repeatedly in my posts, I see no distinction between fight and predation other than our human sense of "fair play." Orcas have no concern with giving a shark a fair fight. Sharks have no concern with giving orcas, FKW's or dolphins a fair fight. A "fair fight" means you are subjecting yourself to greater risk of injury or death. I prefer to concentrate on the actual predatory interactions of species rather than hypothetical MMA matches we like to impose upon the animals. Remember, for the animals this is life or death, eat or be eaten. It's not a situation where the one animal bests the other in a one on one fight and then a referee waives the victor off so the defeated animal can go on its merry way. There aren't "rules" other than "win, die, escape, or be seriously injured." Therefore, in interspecific conflicts, I weigh how animals actually interact, rather than how we humans wish they would act to meet our fantasy conflict scenarios.

[theropod]

I’m not saying that that’s a small FKW or that it’s a juvenile (you are right in that it’s probably pretty normal-sized), I’m saying that it’s most likely smaller than a shark that could reasonably be expected to launch a predatory attack on it. Great white sharks are estimated to mature at around 4-4.5m (Casey & Pratt 1985), so even at the lower range of adult size, a great white would probably considerably outweigh a 3.8m Pseudorca. Based on a variety of regression equations, such a shark would weigh between 543 and 931kg, compare that to 422-446kg for the FKW scaling from recorded weights for captive specimens.

A female captive Pseudorca in the same study was actually 500kg in mass at 10 years of age.

from Long & Jones 1996:


The great whites that attacked them were probably several times more massive than their largest scientifically recorded odontocete prey, at least as of 1996 (but I have seen no record of relatively larger odontocetes being taken), and the whales in question were ziphiids, not raptorial delphinids. The only probable exceptions I know to great whites consistently taking prey smaller than themselves are bull northern elephant seals and neonate right whales.

Based on that I think it’s kind of a stretch to imply that great whites break this general rule with false killer whales of all animals (which as you note, are formidable), even if we accept that they do prey on them. Most likely, a whale like the above example would be attacked by a large, 5-6m shark, which would outweigh it several-fold.
If we just look at whether the species’ size ranges overlap without looking at the specimens…a 5m killer whale (like the one that killed the great white in Pyle et al.’s account) is also within the size range of great whites, not "in a whole different size class" at all. We should apply the same standards here, considering there is just as much evidence (i.e. none) for great whites taking false killer whales of the same body size as there is for orcas doing so.

So by all accounts, orca/great white is a biased analogue, because orcas probably don’t take great whites their own size, but the same goes for great white/fkw, because great whites probably don’t take false killer whales their own size either. So I would certainly disagree with saying that it is "by far" the best analogue. I think it’s about as good an analogue as orca/great white, only a little more frustrating because there are no actual observed interactions.

What I’m saying is that Livyatan was much better armed than a FKW at the same size. I posted the figures in one of my previous posts. If Livyatan’s skull (294cm long) was proportionately as "small" as Pseudorca’s, the holotype would have been well over 20m in length. Assuming the holotype was 15m long, its jaws are larger by about half than those of the delphinid. On the other hand, size estimates assume C. megalodon’s jaws to have been proportionately the same size as a great white’s. So in addition to the proxy being afflicted with the same size discrepancy you correctly criticise in another example, analogizing the two also ignores that one of the two animals, but not the other, actually has proportionately 50% larger, and presumably more powerful jaws.

Of course "fair fights" don’t happen in nature, but both animals would certainly be capable of killing each other in an ambush scenario. I’m not saying predatory interactions are not relevant, but they don’t directly equate to the scenario assumed here, which is what animal would be more likely to succeed without ambushing the other to drastically increase its chances of success. If that’s not a relevant difference, then I’d questions why predators don’t just show up and fight it out with their prey in nature in the first place.

prehistorican : Actually as for orcas charging into a prey item to bite rather than ram, I may have found an example:

Pitman et al. 2001 said:

1100, attacking killer whales broke up the
rosette and isolated two sperm whales. One of these rolled over on its side
and appeared to be nearly dead. At that moment, an adult male killer whale
charged in and slammed into it. The male took the sperm whale in its jaws
and shook it violently from side-to-side. He then spun it around at the surface,
throwing huge sprays of water into the air in an immense display of power
not shown by any of the females at any time during the attack. Several other
killer whales also came in to attack this individual when another sperm whale
came out from the rosette and attempted to lead it back to the formation. In
the confusion that followed, it was not clear which of these two animals was
killed, but shortly afterward the adult male killer whale swam off carrying a
large dead sperm whale with him.

The description reads almost like a shark attack, just with much larger prey. But this is definitely unusual behaviour for orcas.
Generally these accounts seem to involve unusual amounts of biting and gripping, as opposed to ramming. Perhaps a result of the sperm whales being in a group, with the arising need to pull individuals out of formation?

Pitman, R. L., L. T. Ballance, S. I. Mesnick, and S. J. Chivers. 2001: Killer Whale Predation on Sperm Whales: Observations and Implications. Marine Mammal Science 17:494–507.

Attachments:

[elosha11]

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.

[Grey]

With the evidence of right whales calves (weighing about 1 tonne at birth) being targetted by white sharks, I think there is good evidence of larger prey items than juvenile beaked whales than Long & Jones 1996 recorded.

[theropod]

As I already wrote: "The only probable exceptions I know to great whites consistently taking prey smaller than themselves are bull northern elephant seals and neonate right whales."

It’s certainly true that they do on occasion attack prey around their own size, but that does not change the general rule. Odontocetes are also quite a different story from newborn mysticetes or pinnipeds, and might pose more of a challenge for predators. There are few odontocetes where I’d say that situation is more pronounced than with the false killer whale, which is known to prey on other odontocetes and even large whales itself on occasion.

Simply put, if great whites really prey on false killer whales their own size, predation on smaller fkw should be even more common. But shark predation on false killer whales is not common at all, there is not a single confirmed kill. So if sharks prey on fkw, they probably only do it with a size advantage.

I have already demonstrated, a great white preying on a false killer whale could easily be 4-5 times as massive as its prey, which doesn’t constitute a relevant confrontation at similar sizes at all.
Otherwise, following this logic one could argue that since some female orcas are similar in size to large female great whites, and orcas are (confirmed) predators of great whites, orcas could be expected to prey on great whites their own size too.

[elosha11]

Theropod, again I'm going to address your last two posts in detail, as I have time. Working now, so I don't currently have time. But I will quickly post three quotes from the article describing the orca attack on the FKW, because they are relevant both to the current GWS v FKW inquiry and also to Meg v. Liyatan. The below quotes come from here. www.farout.org.nz/images/farout/documents/scientific-articles/Visser%20et%20al%20(2010)%20predation%20on%20Pseudorca%20by%20O%20orca.pdf

00) by a related or nonrelated P. crassidens.
The apparent voluntary leaping observed
during the third attack (Figure 1) may have been
an attempt by the P. crassidens to avoid an underwater
attack, or the P. crassidens may already
have been rammed underwater. The speed with
which the O. orca propelled itself out of the water,
following this P. crassidens, allowed it to make
a substantial physical impact into the side of the
P. crassidens. Figure 1b shows the distortion of
the body of the P. crassidens, which, despite anecdotal
reports of this impact “snapping her back”,1
could not be verified and, given that one of the
authors (TM) observed this P. crassidens swim off
to join the mixed-species group, it seems unlikely
that its back was broken. It cannot be ruled out
that other physical damage (which may or may
not ultimately have been fatal) occurred.

If fleeing is not a viable option to avoid predation
from O. orca, adult P. crassidens may be
physically capable of defending themselves, particularly
if they remain in a group. Cetaceans that
tend to resist attacks may be more likely to survive
attacks than those with more submissive physical
reactions (Steiger et al., 2008), certainly when
compared to species which are less able to fight
back (e.g., Balaenoptera acutorostrata [Minke
whales]: Ford et al., 2005; Ford & Reeves, 2008).
P. crassidens may resist attacks by predators
as they themselves have been recorded harassing
cetaceans, including species much larger than
themselves—for example, sperm whales (Physeter
macrocephalus) (Palacios & Mate, 1996) and
humpback whales (Megaptera novaeangliae)
(Weller, 2002). Immediately following the events
reported here, one of the O. orca (NZOP-003) was
photographed with fresh tooth-rake marks on its
caudal peduncle. It is not possible to ascertain if
they were conspecific rake marks or if they had
been inflicted by a P. crassidens during the attacks.
Given the robust dentition of P. crassidens (Stacey
et al., 1994), there could be substantial risk for a
predator attacking this species

Finally, yet another observation of how uninvolved the male orcas were in the attack and their general lesser agility than females and subadults. To the extent one believes Livyatan was orca shaped, one must acknowledge there would be a sizeable loss of comparative agility, which is already seen in larger male orcas, much less the far larger Livyatan.

Several studies of O. orca predation on marine
mammals note that females and subadults
were active participants throughout the attacks,
but mature males had little or no involvement
(Arnbom et al., 1987; Silber et al., 1990; Jefferson
et al., 1991). Here the attacks were conducted by
individual(s) of adult female/subadult male size,
with the adult male only participating during the
prey-sharing phase. Although Berta et al. (2006)
define O. orca as having the optimum shape in
terms of “fineness ratio” (p. 224) and streamlining,
Ford et al. (2005) have suggested that the
larger body size and appendages of adult males
are likely to have a negative impact on their speed
and manoeuvrability compared to the smaller
females (and we additionally recognize that such
constraints should not affect subadult males).

[theropod]

The degree of involvement of male orcas in attacks appears to be quite variable:

Pitman et al. 2001 said:

The role of the adult male in killer whale predation, especially on large
cetaceans, is not clear (Jefferson et al. 1991) because there are published ac-
counts of them participating (Hancock 1965, Whitehead and Glass 1985),
being peripherally involved (Tarpy 1979, Arnbom et al. 1987), standing by
(Silber et al. 1990), or being absent during attacks on large whales (Cummings
et al. 1972). Vidal and Pechter (1989) reviewed the literature and concluded,
“It appears that marine mammals are successfully attacked and eaten mainly
by the larger, usually adult male killer whales,” and that attacks on larger
whales involving only females and immatures were largely unsuccessful. Sim-
ilarly, Budylenko (1981) stated that, “Initially, the prey is attacked by the
large and strong killer whale males and afterwards, when the prey grows weak,
the attacks are continued by the females and young of both sexes.” Our ob-
servations do not support these assertions. The attacking females and young
in Sighting 2 nearly decimated an entire herd of sperm whales without any
help from adult males. In fact, the male killer whale waited until most of the
work was done before moving in to finish off a critically wounded sperm
whale. In a possibly analogous situation, Schaller (1972) reported that male
lions (Panthera Leo) usually waited for lionesses to make a kill, then they moved
in and used their larger size to appropriate the prey. More observations will
be necessary to determine the specific role the adult male, with his much
larger size, plays in killer whale predation.

I have already quoted the relevant passage in Ford et al. 2005 that is cited in Visser et al. 2010.
The bottomline is that larger animals are less agile than smaller ones, and orcas are no exception.

My question is, what’s the relevance to this discussion? Isn’t it blatantly obvious that size negatively affects agility? That is not a problem only affecting orcas, it’s a problem common to all animals.

[sam1]

..yeah such speculation is pointless since there is scientific data on the speed and agility(yaw, pitch,and roll figures) of sperm whales, as shown in my previous posts.
And I think we can safely put livyatan's respective figures in the same ballpark.
What is left for speculation is the speed and agility of the megalodon.
And if contemporary giant sharks are anything to go by, well..you catch my drift.

[theropod]

Yes, how it compares to megalodon is the question. Sperm whales give us an idea of the kind of mobility we can expect Livyatan would have been capable of. 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.

[elosha11]

Jul 26, 2018 19:33:50 GMT 5 theropod said:

The degree of involvement of male orcas in attacks appears to be quite variable:

Pitman et al. 2001 said:

The role of the adult male in killer whale predation, especially on large
cetaceans, is not clear (Jefferson et al. 1991) because there are published ac-
counts of them participating (Hancock 1965, Whitehead and Glass 1985),
being peripherally involved (Tarpy 1979, Arnbom et al. 1987), standing by
(Silber et al. 1990), or being absent during attacks on large whales (Cummings
et al. 1972). Vidal and Pechter (1989) reviewed the literature and concluded,
“It appears that marine mammals are successfully attacked and eaten mainly
by the larger, usually adult male killer whales,” and that attacks on larger
whales involving only females and immatures were largely unsuccessful. Sim-
ilarly, Budylenko (1981) stated that, “Initially, the prey is attacked by the
large and strong killer whale males and afterwards, when the prey grows weak,
the attacks are continued by the females and young of both sexes.” Our ob-
servations do not support these assertions. The attacking females and young
in Sighting 2 nearly decimated an entire herd of sperm whales without any
help from adult males. In fact, the male killer whale waited until most of the
work was done before moving in to finish off a critically wounded sperm
whale. In a possibly analogous situation, Schaller (1972) reported that male
lions (Panthera Leo) usually waited for lionesses to make a kill, then they moved
in and used their larger size to appropriate the prey. More observations will
be necessary to determine the specific role the adult male, with his much
larger size, plays in killer whale predation.

I have already quoted the relevant passage in Ford et al. 2005 that is cited in Visser et al. 2010.
The bottomline is that larger animals are less agile than smaller ones, and orcas are no exception.

My question is, what’s the relevance to this discussion? Isn’t it blatantly obvious that size negatively affects agility? That is not a problem only affecting orcas, it’s a problem common to all animals.

There's significantly more evidence suggesting that male orcas are less speedy and agile than females and subadults than vice versa. Your quote above refers to attacks on large ceteceans, presumably larger than the orcas. In that case, the bulk and power of male orcas comes into play more obviously. But when chasing smaller, and more agile prey, it appears females and subs take the lead. Of course, that doesn't mean males aren't still very fast and agile, and obviously more powerful than their smaller mates. But the idea that even at male sizes the orca body type is "slowing down" is easily relevant to the conversation b/c it provides clarity. I'm a bit skeptical that Livyatan was shaped exactly like an orca but if one wants to argue that, we just need to be clear that there will be constraints related to that shape and size. And of course that applies equally to Megalodon, it would not be as agile as a GWS with a similar fusiform body type. I'm not as inclined to believe Megalodon was shaped like a whale shark or even a basking shark, their general body shape and tail shape (particularly whale sharks) are not optimal for a predatory lifestyle. If we can ever get complete review of a Meg skeleton or partial skeleton, we may be closer to answering these questions.