Megalodon vs. Livyatan melvillei

[prehistorican]

May 27, 2018 0:23:29 GMT 5 Grey said:

I confirm it is reasonable to consider the gigantic jaws reconstruction made by Vito Bertucci as scientifically credible.

The first of this reason is that beside Shimada, all the fossil sharks specialists I've talked to about this jaw weren't critic of this reconstruction.

Shimada once said the size of the teeth in the reconstruction was decreasing far too slowly.

But I strongly suspect Shimada only had in mind the smaller Bone Valley dentition, which indeed has a decreasing size of its teeth faster than what Bertucci made in his reconstruction.

However, Shimada quite probably didn't have in mind, or perhaps didn't examine the Aurora larger dentition. This dentition definitely have a far slower decreasing rate of the size of its teeth. In fact, using GimP on high resolution pictures of the Bertucci reconstruction, it appears the Aurora dentition has an even slower decreasing rate. Which means that if Bertucci had modeled his reconstruction on the Aurora set of teeth, it could have been even a bit larger than that.

Stephen Godfrey also considered the jaws to be reasonable.

Of course, Bertucci jaws are directly based on the great white jaws architecture and made in an unatural position, like many trophee sharks jaws.

But at the very least, the size of the teeth of this composite is perfectly reasonable.

To me, this confirms this mouth quite more massive than the one in Livyatan.

Not too much of a surprise when the Houston Science Museum Megalodon Jaws are displayed (I forgot the builder however, not sure if that matters).

[Grey]

The builder is Clifford Jeremiah, I got an email from him. He also helped Bertucci on his reconstruction, hence the very similar shape.

[prehistorican]

Ah yes, however Vito's has a 12 foot diameter while the one in Houston has a 11 foot diameter I believe. I always knew Megalodon had a larger jaw, it seems to have been able to take on larger prey and I think there was a front half of a 50 foot whale (probably torn in half by Megalodon) and of course the famous decpitated whale. Livyatan seems to be better at crushing smaller whales of up to maybe 21-30 feet long? I would definitely favor the shark if we go by upper estimates of both animals. 100 ton shark vs 60 ton whale? No question who is going to win.

[elosha11]

^Well, I don't know if I'd personally go as far as to say no question who's going to win. Nor am I convinced the size disparity is greatly in favor of either animal. There's just so much we don't know about Livytan. I will state, very cautiously, that Megalodon may have exceeded 18 meters (the usual consensus size among most researchers), and may have actually exceeded 18 meters by quite a lot. The thought-provoking work by Grey and his colleagues certainly suggests this, but I would like to see what, if anything, other peers will have to say about it, if/when their research becomes more widely published.

As to whales, I am currently remembering three to four whale fossil skeletons that show Meg bite marks. Those are the 30 foot whale examined in New Scientist article "Hell's Teeth," the 25-30 foot baleen whale (fossil skull) recently found in Virginia riverbed with Megalodon bite marks, the 25 foot skeleton found in Shark tooth Valley and featured on SharkWeek "Sharkzilla" documentary, which appeared to be bitten in half by Megalodon, and lastly pictures Life has posted here before of a partial whale vertebrate and skeleton with huge bite mark damage from Megalodon. I've heard anecdotal evidence of whale skeletons bitten in half in the Ica desert in Peru, but those are not confirmed.

I'm not aware of any fifty foot skeleton bitten in half, so please let me know if this is some new source. That would be quite exciting.

[prehistorican]

May 29, 2018 0:39:01 GMT 5 elosha11 said:

^Well, I don't know if I'd personally go as far as to say no question who's going to win. Nor am I convinced the size disparity is greatly in favor of either animal. There's just so much we don't know about Livytan. I will state, very cautiously, that Megalodon may have exceeded 18 meters (the usual consensus size among most researchers), and may have actually exceeded 18 meters by quite a lot. The thought-provoking work by Grey and his colleagues certainly suggests this, but I would like to see what, if anything, other peers will have to say about it, if/when their research becomes more widely published.

As to whales, I am currently remembering three to four whale fossil skeletons that show Meg bite marks. Those are the 30 foot whale examined in New Scientist article "Hell's Teeth," the 25-30 foot baleen whale (fossil skull) recently found in Virginia riverbed with Megalodon bite marks, the 25 foot skeleton found in Shark tooth Valley and featured on SharkWeek "Sharkzilla" documentary, which appeared to be bitten in half by Megalodon, and lastly pictures Life has posted here before of a partial whale vertebrate and skeleton with huge bite mark damage from Megalodon. I've heard anecdotal evidence of whale skeletons bitten in half in the Ica desert in Peru, but those are not confirmed.

I'm not aware of any fifty foot skeleton bitten in half, so please let me know if this is some new source. That would be quite exciting.

Nah, probably wrong I guess, there was a whale front half that was missing in Peru. Some shark tooth hunter just said it was probably from a Megalodon, since it was the only animal large enough to slice a whale in half, but it could have been erosion too. I found it in some blog, where a man travelled to Peru to view the large shark teeth. So unreliable at best I guess, now that I think about it.

[Grey]

That was the article of Gail Harrington who met Roberto Cabrera who showed this alleged whale skeleton.

[sam1]

Replying to this piece written by Ausar in another thread:

"Why is Livyatan's ramming ability "the most defining aspect of this clash"? I'd expect that to be the case if we were talking about Physeter (at least as the whale's most defining aspect), but not Livyatan. Not with the thick jaws, large room for jaw-closing muscles on its nearly 3 meter skull, and teeth the size of 2 liter soda bottles. Especially not if Livyatan, if anything, had a relatively smaller supracranial basin, and therefore a smaller junk and spermaceti organ. This is not to say Livyatan could not and will not try to effectively ram, it certainly can and will. The point is that it's not going to be this fight's "most defining aspect".

Think about the scenario Sam described in his post:

"Quite simply, in an equal term confrontation ,the shark is the one forced to go into defensive reaction, evading the charging whale.
Beyond that point, the whale has the initiative as it can pursue megalodon forcing it into constant retreat , because exposing the sides and back to this whale would be very dangerous, not so much from the damage of the bite per se, but actually Livyatan's ability to grip and hold onto Megalodon's hind quarters, underside and pectoral fins..fins being the most critical parts because of their vulnerability from all angles. If the whale grabs one, it should've been able to tear it off easily - and consequentially kill the meg.(causing it to drown).
And what makes all of this feasible and likely instead of just a theory imho, is whale's far superior intelligence, maneuverability and body control."

What if Livyatan wanted to bite the shark instead? The scenario would pretty much be the same as above (in fact, in the description above of how the fight will go, the whale does end up biting the shark). The shark isn't any more or less able to evade such an attack as it would if Livyatan decided to ram, and both would result in a dead shark if the whale succeeded.

What if the scenario is reversed and the shark is the one who swims towards the whale to attack? Pretty much the same thing, no? Only difference is that the shark will be tearing chunks out with its teeth and huge jaws. And if O. megalodon indeed rammed its prey too, same thing, no? So why is ramming the "most defining aspect" when choosing to bite will result in just about the same thing?

I guess the only thing that's up for question with everything I've addressed and mentioned above is which is more or less able to evade an attack from the other. Sam1 suggests the whale is more maneuverable with greater body control, but it seems not everyone agrees."



Those are some valid observations, but I just see a ram at full speed as a more potent and efficient way to gain initiative. The bite is a follow up.
Keep in mind that a 40-50ton body charging at around 30km/h and clashing with another body of similar mass would result in a massive kinetic energy release..and such energy needs to be received with the forehead, not by jaws.
Remember the Brygmophyseter vs Megalodon CGI animated episode? The two brygmophyseters(over sized, I know, but that's besides the point) charged and rammed the megalodon

[elosha11]

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.

[sam1]

Elosha, just have to quickly let it be known that I fully appreciate the time, quality and effort you put into your posts. It does not go unnoticed.
I should have time and peace of mind next week to respond in a more deserving manner.

[elosha11]

Sure take your time. I sometimes take weeks before responding to posts, so no hurry.

[sam1]

Alright.
So, after further consideration and some more reading, I have to admit that I don't have much to say to defend my position about Pseudorca actually..the relative lack of material about these dolphins doesn't help my case. So it's all down to guessing. And I could well be very wrong in my view of how some things are playing out.
While I agree with you that morphologically,
the pseudorca and GWS seems like the best real life analogy to livyatan and megalodon, the vastly different size categories ultimately paint a completely different picture.
Like I said, I feel like ramming would be the most defining aspect in a clash between livyatan and megalodon..but in a clash between great white and false killer, it is probably far less so.
It's like comparing bumper car collision with tow truck collision. The same thing, but very different consequences.

[sam1]

..oh and about the alleged case of great white attacking and killing an orca, yeah that's the one you mentioned.
I also couldn't find any concrete information.

[elosha11]

Thanks Sam. Prehistorican said in another thread recently that he saw some article from the early 1900's about a great white shark attacking a sick bull orca. The orca was said to be about 6 meters long, so fairly small. But he doesn't remember where he saw the source either. Grey has mentioned seeing this too. It's odd that the article is so obscure; I've certainly never been able to find it.

As far as FKW and great whites, I take the limited data with a grain of salt. I would't argue it is a huge factor in predicting interactions between Meg and Livy. I agree with you that the sheer differences in size between the species makes any extrapolation and modern analogy very dicey. And yet, I also agree with you that it's still probably the best modern equivalent. So the best we can say is the data is inconclusive. All we know is that large sharks appear to infrequently engage in predatory attempts on FKW's. I also note that large sharks may infrequently attempt to prey on pilot whales. Although they are actually bigger than FKW's, I consider them less formidable with much smaller teeth and much less macropredatory feeding habits. Pilot whales are an even more problematic analogy to Livyatan and Megalodon.

[Life]

elosha11

Megalodon was different from modern sharks in anatomy and behavior; it evolved for big-game hunting. Great white shark's behavior is not a filler in this debate.

Megalodon was aggressive and crunched on anything that moved. We have following cases to consider:

www.paleodirect.com/wh023-largest-complete-fossil-sperm-whale-tooth-with-megalodon-shark-bites/
insider.si.edu/2011/11/details-of-ancient-shark-attack-preserved-in-fossil-whale-bone/

This assertion: "All we know is that large sharks appear to infrequently engage in predatory attempts on FKW's. I also note that large sharks may infrequently attempt to prey on pilot whales" - doesn't fit the bill in regards to Megalodon.

It is rare for modern sharks to attack a baleen whale as well.

[elosha11]

^Life, I'm not suggesting the great white is a filler or a stand in for Megalodon in this debate, nor that FKW's are adequate proxies for Livyatan. Just simply pointing out that given their comparative sizes and formidable nature, great white sharks and FKW's are the best - albeit very limited - comparison we can make. If there's any tenuous conclusion to draw from the limited data, it would be that modern large predatory sharks will at times seek to prey upon similar-sized toothed cetaceans. Whether that has any impact on how people judge Meg v. Livyatan contest is up each individual's weighing of the evidence.

It is rare for modern sharks to attack baleen whales but that's obviously because of vast size differences. That wouldn't be nearly as great a concern for Megalodon or C. Chubutensis.

I think it likely that Megalodon at times preyed on prehistoric sperm whales, as evidenced by bite marks on their fossil bones. Keep in mind sperm whales are thought to be somewhat smaller back in the Miocene/Pliocene. Whether this predation extended to Livyatan as well is unknown.