Prehistoric Sharks

[GuateGojira]

(06-30-2023, 07:34 PM)Apex Titan Wrote: @Spalea  @GuateGojira 

I'll respond to you guys later when I have time.

I was already reading your posts and debate in other Megalodon topic, and been honest you are severily overestimating this animal. Like Spalea said, we know that this is a huge apex predator, but you describe it like an invincible war machine, which is not the case.

Again, like I said to another poster, I don't care about Megalodon because, for me, is just a case of back and forth, we only have its tooth and some vertebrea and that is all, and from that is just pure speculation, its size change every new document and even the new articles that you quote shows a huge bias and lack of knowledge of the same authors, stating things like megalodons eating orcas like snacks, when orcas (modern ones at least) don't even lived with Megalodon. In fact, new hypotesis says that it was the white shark, smaller than the orca, which could help to drive the huge Meg to its extintion.

When I read those news articles I don't know if I am reading a sceintific article or guy trying to sell something. Too much sensacionalism, I will prefer to read the original documents, been honest.

EDIT: I know where this is going. Honestly I just returned from several months and the last thing that I want it to discuss something irrelevant like this. So, I will leave this now, if someone what to believe that Meg was the terminator of the seas is ok, I simple don't care. I will focus in what I DO CARE, which are tigers and other modern animals. I leave the debate to the other posters. Reply

[Apex Titan]

(06-30-2023, 06:14 AM)GuateGojira Wrote:

(06-29-2023, 06:31 PM)Apex Titan Wrote: There's no way that a single Leviathan would be able to defeat multiple large male megalodon's. That video is highly unrealistic and ridiculous. Leviathan was just an ancient sperm whale with much larger teeth and more predatory, but would be no match for an adult megalodon. The megalodon was larger, more powerful and more lethally equipped for killing than any other ocean predator ever.

IMHO, the only way the Leviathan whale would stand a chance, is if a whole pod attacked a single megalodon.

@Spalea I want your honest take on this as well.

I have a question... according to the general consensus of the worlds foremost marine predator experts, researchers and paleontologists, nothing in the ocean could have taken on a megalodon, nothing could have challenged it, so why do you think they say this?

You might find maybe one expert who thinks a Leviathan may stand a chance or being capable of defeating a megalodon, but the vast majority of the worlds marine predator experts adamantly state that the megalodon was the undisputed apex predator and ruler of the prehistoric ocean and could have killed anything it wanted to. Recent scientific research also shows this.

The Leviathan (Livyatan Melvillei) doesn't get mentioned by the experts (even in documentaries) for a good reason. Only on animal forums do posters mention the Leviathan to be a "worthy opponent" for a megalodon. Why?

Prehistoric animals are a mystery, best thing we can do is to try to study modern animals and see how they could correlate with the past ones. It sounds simple but there are several problems, as many of the past animals are just far related with the modern ones and we know that modern animals had particular behavious that we will not knew if we could not observe them directly.

The video is just a fan art, nothing more and nothing less, no more valuable than the Rex vs Spino fight in JP3. We can't avoid people express they ideas, I learned that in the hard way.

But talking about the real animals, we don't know if these species were solitary or if lived in groups, and we can only "guess" based in modern species. Most of sharks are solitary and they just come in groups when there is a good food source like happen with the white and tiger sharks, so we can guess that most of the time Carcharocles (otodus) megalodon was solitary but we can also guess that they could tolerate each other under special  circunstances. About Livyatan melvillei we have the same problem, we can say that modern whales are groupal, but that is an oversimplification and even social animals like orcas have individuals (large males most of the time) that travel alone, and to add more salt to the soup, the modern relatives of this species, which are the two genus of sperm whales, have completelly different behaviors, so we can guess that as they are cetaceans they could travel in groups of "pods", but if they are like modern Physeter, males will be loners. So, as you can see, this is just a game of probabilities, based in more or less closer relatives, and the evidence suggest a behaviour contrary to what we see in the video. In fact, I will suggest that the video should be a big Megalodon killing young and female Livyatans until a big male arrive and kill it, that will have more sense honestly. 

Now about the experts and why Livyatan is not mentioned. Honestly, tiger supporters had the same problem with the romans, if tiger won must of the fights why the romans supported the lion as the most powerfull cat? Well, the answer was simple, tigers were know in Europe until the time of Alexander the great and was only one skin, and alive tigers arrived to Rome like a gift to Augustus until year 11 B.C.E. for the dedication of the Theater of Marcellus. In fact, no more than 200 tigers were presented to the Romans in all they history, a ridicuous amount if we take in count that romans killed more than 300 or even 500 lions in just one show, and they had many of this shows! Lions were highly familiar to the Romans, and the new arrival was no match for the imagination and "love" for the old signs, so tiger were never familiar to the Romas as lions do. Now, it you ask to any marine predator experts about what is a Livyatan, I can tell that not all of them know about it, in fact prehistoric marine mammals are highly unknown to many experts and also most of the people outside, remember that we have less than 10 papers that mention it (only 4 specific about it) while on the other hand Megalodon is incredible famous, almoust like T. rex. To put other analogy, ask people about Mapusaurus and they will have no idea what you are talking about. We have no documental, no movie, nothing about Livyatan, or any other prehistoric cetacean, apart from Basilosaurus and maybe Brygmophyseter (and this last one was baddly represented), so there is no surprise why there is a "consensus" that Megalodon is the "champion". But this is going to change in the future years, now that the knowledge is been shared at higher speed and more people is knowing about the prehistoric cetaceans. In fact, there is many people that is surprise to know how small where the first whales.

So, playing the card that "most of experts" or that documentaries/movies "adamantly" show that Megalodon is the undisputed king is not correct, because you are just taking advantage of the circumstances and the lack of knowledge, basically using a falacy to back up a statement without base.

If you going to back up an statement you must use facts, and there are no facts that Megalodon "won" agains Livyatan, or the other way around. The only thing that we know is that these two animals were the top predators of they area, that they compete for the same resources and that at the end both whent extinct. Also, remember that marine predators must of the time hunt smaller animales than themselves (orca is the exception, when hunt in groups), and "if" Livyatan lived in groups, with a similar size than the average sized Meg, probably the big shark will avoid  those pods of cetaceas and focus in the more easy prey like the "small" Cetotheriums. But all this is just speculation at the end, although based in the behaviour of modern animals.

I am not going to touch the point about sizes as is a real mess, because the "Meg" change every new study, and for "Liv" we have only one "official" estimation. However, at least, one more-or-less complete skull is better that a bunch of teeth and a lot of speculation, I think.

I know prehistoric animals remain (and always will) a mystery, however, recent scientific research strongly indicates that the megalodon was indeed the ultimate apex predator of all time. According to the evidence, the megalodon occupied the absolute highest position in the food-chain and regularly killed and ate other predators and super-predatory animals.

No surprise then that recent research by palaeontologists at Princeton University in the US has shown that megalodon ate whatever it wanted – including other predators. The results of the research, published in Science Advances, indicate this ancient shark was an apex predator with no comparison in all of Earth’s history.

“We’re used to thinking of the largest species – blue whales, whale sharks, even elephants and diplodocuses – as filter feeders or herbivores, not predators,” says the paper’s lead author, geoscientist Emma Kast, now based at the University of Cambridge, UK. “But megalodon and the other megatooth sharks were genuinely enormous carnivores that ate other predators, and Meg went extinct only a few million years ago.”

“If Megalodon existed in the modern ocean, it would thoroughly change humans’ interaction with the marine environment,” adds senior author Danny Sigman, professor of geological and geophysical sciences at Princeton.

Kast and Sigman’s team discovered clear evidence that megalodon and its ancestors occupied the highest rung of the prehistoric food chain – called the highest “trophic level”. So high is their trophic signature that the researchers believe megalodon must have eaten other predators and predators-of-predators in a complicated food web.

Helping megalodon on its way to the top of the food web is cannibalism. There is evidence of cannibalism in both megatooth sharks and other prehistoric marine predators.

“Ocean food webs do tend to be longer than the grass-deer-wolf food chain of land animals, because you start with such small organisms,” says Kast. “To reach the trophic levels we’re measuring in these megatooth sharks, we don’t just need to add one trophic level – one apex predator on top of the marine food chain. We need to add several onto the top of the modern marine food web.”

https://cosmosmagazine.com/history/megal...-predator/

A May 2022 study revealed that great white sharks which coexisted with the megalodon preyed on the same animals, causing competition between the two species, which may be one of the factors how the megalodon went extinct. But even so, a more recent study shows that the megalodon is the ultimate apex predator that ever ruled the oceans.

According to Daily Star, researchers examined thousands of shark teeth to prove that the megalodon is the ultimate apex predator, surpassing records of other marine predators. Dr. Emma Kast, the first author of the study, said that megalodon teeth show that megalodon was indeed an enormous carnivore that ate other predators but went extinct a few million years ago.

To know that megalodon sits at the top of the food web, scientists looked at the nitrogen in recovered fossil teeth. The more nitrogen-15 it has, the higher its trophic level. Their findings show that megalodon sharks hunted around the world at the very top of a global marine food chain.

https://www.sciencetimes.com/articles/38...ggests.htm

Here's the scientific studies:

https://www.science.org/doi/10.1126/sciadv.abl6529

https://www.science.org/doi/10.1126/sciadv.add2674

https://www.princeton.edu/news/2022/06/2...-predators

Why would the video make "more sense" if a big male Livyatan whale comes and kills the big megalodon??  What makes you think a single Livyatan whale could kill a megalodon in a one-on-one encounter? I honestly can't imagine that happening, after all, it's just a predatory sperm whale! It makes much more logical sense for megalodon to kill the large male Livyatan whale. Megalodon was literally a specialized whale-killer. It was specifically built for this purpose and highly adept at killing even large whales.

No, I'm not playing the card: "most of the experts" or because "documentaries show" it, I've clearly been referring to the most recent scientific research, peer-reviewed studies, which strongly suggest that the megalodon was indeed the greatest and most formidable apex predator of all time and was the undisputed top marine predator - ever.

Forget the movies, I'm not referring (and never was) to Hollywood crap.... what do the marine scientists, researchers and biologists say? What do recent scientific studies show about megalodon? This is whats important. I don't know why you're mentioning movies.

I'm taking advantage of circumstances and lack of knowledge?? Using fallacy to back-up a statement without base? Are you serious?? All this time, I've been referring to scientific research/studies conducted by marine scientists, researchers etc, which clearly indicate that the megalodon was the highest-level apex predator - ever.

Why don't you just read the studies and articles and see why the experts came to this conclusion? Reply

[Apex Titan]

(06-30-2023, 08:22 PM)GuateGojira Wrote:

(06-30-2023, 07:34 PM)Apex Titan Wrote: @Spalea  @GuateGojira 

I'll respond to you guys later when I have time.

I was already reading your posts and debate in other Megalodon topic, and been honest you are severily overestimating this animal. Like Spalea said, we know that this is a huge apex predator, but you describe it like an invincible war machine, which is not the case.

Again, like I said to another poster, I don't care about Megalodon because, for me, is just a case of back and forth, we only have its tooth and some vertebrea and that is all, and from that is just pure speculation, its size change every new document and even the new articles that you quote shows a huge bias and lack of knowledge of the same authors, stating things like megalodons eating orcas like snacks, when orcas (modern ones at least) don't even lived with Megalodon. In fact, new hypotesis says that it was the white shark, smaller than the orca, which could help to drive the huge Meg to its extintion.

When I read those news articles I don't know if I am reading a sceintific article or guy trying to sell something. Too much sensacionalism, I will prefer to read the original documents, been honest.

EDIT: I know where this is going. Honestly I just returned from several months and the last thing that I want it to discuss something irrelevant like this. So, I will leave this now, if someone what to believe that Meg was the terminator of the seas is ok, I simple don't care. I will focus in what I DO CARE, which are tigers and other modern animals. I leave the debate to the other posters.

I never once said or implied that megalodon was "invincible". I clearly said, more than once, that a whole pod of Livyatan's are capable of defeating or withstanding a single megalodon. Just because someone says that the megalodon was the undisputed king of the ocean and the greatest apex predator ever, doesn't mean that person is also saying or implying that the megalodon was simply an "unstoppable war machine" which was completely "invincible" or something. No, thats not what I'm saying.

For example, tigers are the undisputed top predators of Asia, and yet they can be killed by other large, dangerous animals such as adult elephants, rhinos, gaur, wild buffaloes who defend against their attack. When wildlife experts call the tiger: "Undisputed Lord of the forest", "Master, owner or Lord of the taiga" etc, does that mean they're implying that the tiger is an "invincible war machine" that can't be killed by another dangerous animal? Of course not.

IMO, (and the opinion of many wildlife experts) the tiger is the ultimate terrestrial apex predator on earth, but does that mean I think the tiger is an "invincible war machine"?? Of course not.

In every major ecosystem (prehistoric era & modern era) there's always been a top predator that reigns supreme over all other animals. This top apex predator will regulate prey and predator populations. This is how nature works. There's almost always a "king" predator at the very top of the food-chain. In the jungles, mountains & forests of Asia (including far east Russia), we have the tiger who reigns supreme, in the open grasslands/savannah's of Africa, we have the lion who reigns supreme, in the Arctic lands, we have the polar bear, in North America we have the gray wolves, brown bears and cougars, and in the Amazon we have the jaguar who rules. In the modern oceans, we have the orcas who reign supreme.

In the prehistoric ocean, the megalodon was certainly the undisputed top predator at the very pinnacle of the marine food-web, and could have killed and eaten anything it wanted to. And the recent studies indicate so.

I honestly think you're highly exaggerating the Livyatan whale. IMHO, it's just a glorified sperm whale, nothing more. Megalodon probably killed and ate Livyatan whales at times:

*This image is copyright of its original author

https://theconversation.com/megalodon-sh...ion-185118

Due to the megalodon's highest position in the food-chain, it most likely hunted and killed Livyatan whales. 

Remember, what I say about megalodon is not just an opinion of mine, I'm referring to expert authorities, scientists and marine researchers who are adamant, based on scientific studies, that the megalodon was the undisputed top predator of the ocean and could have killed anything in the prehistoric oceans. Reply

[Apex Titan]

(06-30-2023, 02:00 PM)Spalea Wrote: @Apex Titan :

Well, @GuateGojira has magistrally answered in my place. What could I add ? I didn't want to make you angry or to cast doubt systematically what you tell. I only ask a few questions, always the same... You say that the biggest megalodon specialists think as you do. Perhaps yes, but I don't care of their assertions  and stay with my doubts.
Of course this video seems to be ridiculous in your opinion. It isn't a scientific video of course, it has no one scientific value, but I find it good made. With little means, we just feel sperm whale's and shark's skins. Very realistic, I have even a deeper appreciation as concerns these videos about dinosaurs and terrestrial animals. But that 's an other subject.
About megalodons I always only stated on this: they were cartilaginous fishs. So in other words, no one possible fossilization of the bones, except the teeth. And about teeth what can we do ? To compare them with the actual tiger and white shark's teeth. And to make or estimate a volume ratio. And from that, estimating the megalodon's weight. Simple isn't it ? No because we don't stop reading some extrapolations, some always growing extrapolations could I say. I just say it changes everything according to whether the meg weighed 20 or 65 tons (your last estimation). In the first case, the megalodon had to sustain a competition with other huge predators, in the second case it completely destroyd the concurrency. You're seemingly adopting this last hypothesis, adult megalodon was invincible. And not an indolent shark as you told in a previous thread. OK ! How, in this case, this specy could have been roaming so much time, 20 millions years, inside oceans ? I only see one possible explanation: megalodons were extraordinary scarce. An invincible predator systematically killing big preys and other big predators cannot have a geological duration of life (look upon us ! We are quickly going towards our extinction with our actual bullshit) except because of its extrem scarcity.
So, what was the limitating factor of its population ? Extremely low rate of reproduction ? Perhaps... A  worm is in the fruit.

Why would I get angry?? We were having a nice, friendly discussion about megalodon, thats all. No big deal. At the end of the day, you have the right to your opinion. If you don't agree with me, thats fine.

But once again, I never said the megalodon was "invincible", not once. I already told you that I think a whole pod of Livyatan whales were capable of defeating or withstanding the shark. One-on-one, its a totally different story.

A recent article (June 27, 2023) was published about the possible reason for megalodon going extinct:

"But the shark’s voracious appetite may have also spelled the species’ ultimate doom. Gigantism has a high metabolic cost, says UCLA marine biogeochemist Robert Eagle: Bigger bodies require more food, and the massive sharks may have been particularly vulnerable to extinction when the climate changed and food became scarcer."

https://www.sciencenews.org/article/mega...leontology

As for the other stuff about megalodon, have you read the actual studies I posted?  Do you know why the marine scientists came to that conclusion about megalodon? And why do you think they're wrong? Reply

[Spalea]

@Apex Titan :

About #49: Interesting article you posted ! It reminds me how we stated that big dinosaurs (sauropods) were not cold-blooded animals. At first, we thought that they lived into the swamps, lakes and so on, beause they were too heavy to live on the ground. Then we objected that their aerodynamic body wasn't compatible for a way of life like this (very long neck and so on, they didn't look like hippos for example), thus we deduced they were endothermic because of their gigantic size and lived on eath like the extant big herds of herbivors in Africa... A 360 degrees process of reflexion and a final opposite conclusion.

Now, I'm just making one assumption. I imagine the Megalodon being endothermic too. An endothermic 65 tons predator is indeed constantly searching for big preys and have the metabolism to travel through the oceans, because its needs for food are much more higher than an ectothermic one. In short it was always feeling hungry. But I think, for having ruled over 20 millions years through the oceans, it should have been very scarce - otherwise it would have all exterminated. How ? Perhaps because of a very high level of mortality. Perhaps the mother megalodon slaughtered the whole offspring except one or two lucky ones fastly becoming almost immune to predation...

If you say a whole pod of leviathans was indeed capable to defeat a megalodon, it would have not happened very often. Not enough to be considered as being a regular predation. Reply