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Megalodon
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20-03-2012 3:43amNow that I think about it, this board is missing a thread dedicated to discussion of the largest, scariest, most powerful predator known to science. I adore dinosaurs, but the truth is C. megalodon beats pretty much anything else in the fossil record when it comes to monstrousness. At estimated 16-20 meters long, it was probably as long as the very largest theropods (Spinosaurus and possibly others yet to be discovered), yet it weighed between 50 and 100 tons- compare to the largest theropods that weighed between 6 and 10 tons, with some estimates for Spinosaurus at around 20 tons.
So let the debate begin about the mysteries surrounding Megalodon; what do you think it looked like? Was it just a scaled up version of the great white, as usually depicted, or something stranger? Why did it become extinct? Are you one of those people who believe it may still be alive today?1
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I think if we are to look at it's teeth, then the closest animal today in terms of similarity is the Great White.
Personally I think it would be like a Great White on steroids in terms of look.
In terms of why it became extinct. The most common theory is that whales migrated into colder waters near the Poles, but I don't quite buy that every whale went to live by the Poles until the Megs died out. I think it is more likely that during the last Ice age the average water temp may have became a Meg unfriendly factor. But then again I look at some of the modern day sharks, specifically the species that live or have been recorded in colder waters (Great White, Greenland Shark etc) and they are generally large sharks and they survive with ease in the colder waters. So for my comment about the Ice age to have any truth the average water temp in open waters would have to have been very low indeed.
Also there is another problem with the most common theory of whales heading to both Poles and starving the Megs. That theory would rely on there being enough plankton (along with other food types in the food chain) at both Poles to sustain massive whale populations all year round.
Another idea might be that the Meg was simply too perfect a predator. The only thing that could probably have killed a Meg was a bigger Meg. Pretty much everything in the sea would have been on the menu. Maybe it was a case of nature enforcing her own checks and balances. Predator gets so big and efficient that nature cannot replenish prey species fast enough. Predator dies off or evolves into a smaller species (GWS)
One thing I am pretty confident of is that early man was around at the same time, and the Meg was a fairly recent extinction (as in it happened 10,000 to 30,000 years ago at most).
Most admit I am a sucker for the Meg fiction books out there like Alten's Meg series or Rudd's The Arc.0 -
In terms of looks I recall seeing in a documentary that megalodon would have needed to be slimmer/more streamlined than a great white to hunt efficiently at such a massive size. The recreations looked more like a big toothed mako than a great white.
One interesting hypothesis about megalodon's extinction is linked with the emergence of killer whales which are believed to have out-competed and possibly even hunted juvenile megalodon.0 -
In terms of looks I recall seeing in a documentary that megalodon would have needed to be slimmer/more streamlined than a great white to hunt efficiently at such a massive size. The recreations looked more like a big toothed mako than a great white.
One interesting hypothesis about megalodon's extinction is linked with the emergence of killer whales which are believed to have out-competed and possibly even hunted juvenile megalodon.
Don't go along with the Mako comparison if we are to take some of the lower weight estimates of the Meg to be accurate. The lower end of the size estimates for the Meg have been in the 35ft to 40ft range and weighing in the 10 to 20 ton bracket. You just are not going to get a slim shark with those estimates. You are getting a heavily build powerful animal. Plus the size and shape of it's teeth would also suggest a fish with a heavy/powerful build.
Have heard the Killer Whale theory a few times alright. But I don't think it holds much water if one looks at how long the Killer Whale (and it's direct ancestors have been around).
We know from carbon dating on Meg teeth (or rather what is left in place of the teeth) that it is became extinct in fairly recent times, but the Killer Whale lineage has been around for over 10 million years so one would expect them to have done in the Megs a long time before the Meg actually vanished.
Whilst an Orca pod is indeed a formidable hunting machine, not all Orca will feed on larger animals than itself. There is actually a pretty defined and differing food preference depending on what sub species of Orca they are.
Now whilst there have been rare recordings of an Orca pod trying to take on a young Sperm whale or a small female, generally they avoid Sperm Whales and never try it on with a Bull sperm whale, and in a Megaladon we had a shark that may have been similar in size to a Bull Sperm whale and that had the tools to defend itself.
Orca may have taken young Megs, but then again young megs would be Great white sized fish, and although Killer Whale can kill a GW (and there are a couple of recorded cases of this) they don't seem to do it very often, and the cases in which it has been observed have always had adult orca with young.
If I had to guess I would go with water temps being the cause of the Meg going extinct, but it certainlt would have required an average global water temp far colder than that which the large sharks nowadays can tolerate.
Would really love to see a Meg tooth that was still white get found though.:D0 -
Would really love to see a Meg tooth that was still white get found though.:D
I wouldn't!
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Just don't be a dumb ass on a jet ski and you will be fine.
Also avoid folk who ask you to go onto a wooden pier, with some chain, a hook, the sunday roast and a tyre.:D0 -
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One thing I am pretty confident of is that early man was around at the same time, and the Meg was a fairly recent extinction (as in it happened 10,000 to 30,000 years ago at most).
Based on what evidence? Most estimates I've seen have placed it's extinction at 1 million years ago or more.0 -
Based on what evidence? Most estimates I've seen have placed it's extinction at 1 million years ago or more.
Carbon dating on some of the fossil teeth found in Australian waters have given a potential extinction date of between 30,000 to 10,000 years ago. I am too lazy to go upstairs right now but in Great White Shark by Richard Ellis and John McCosker , there is a full chapter devoted to the Megaladon with reference made to the carbon dating of some of the fossil teeth that have been found.
Obviously it is not conclusive, but many now think the 1 million + years date is quite a bit off of the mark.0 -
I thought the recent looking fossils were not held in high esteem among the palaeontological community? I forget where, but I heard they had been more or less discredited.0
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Carbon dating on some of the fossil teeth found in Australian waters have given a potential extinction date of between 30,000 to 10,000 years ago. I am too lazy to go upstairs right now but in Great White Shark by Richard Ellis and John McCosker , there is a full chapter devoted to the Megaladon with reference made to the carbon dating of some of the fossil teeth that have been found.
Obviously it is not conclusive, but many now think the 1 million + years date is quite a bit off of the mark.
I'm guessing by that time Megalodon must have been rare, and that's why not many recent teeth are found? Or maybe just not enough teeth have been properly dated...Don't go along with the Mako comparison if we are to take some of the lower weight estimates of the Meg to be accurate. The lower end of the size estimates for the Meg have been in the 35ft to 40ft range and weighing in the 10 to 20 ton bracket. You just are not going to get a slim shark with those estimates. You are getting a heavily build powerful animal. Plus the size and shape of it's teeth would also suggest a fish with a heavy/powerful build.
I agree. I've read that it would have a short, less conical snout than the great white shark or makos as well. Basically it would be more mouth than nose :cool:Whilst an Orca pod is indeed a formidable hunting machine, not all Orca will feed on larger animals than itself. There is actually a pretty defined and differing food preference depending on what sub species of Orca they are.
Now whilst there have been rare recordings of an Orca pod trying to take on a young Sperm whale or a small female, generally they avoid Sperm Whales and never try it on with a Bull sperm whale, and in a Megaladon we had a shark that may have been similar in size to a Bull Sperm whale and that had the tools to defend itself.
Never say neverI have read reports of orcas hunting large bull sperm whales too. They are not to be underestimated. That being said, sperm whales are probably slower (and have much less formidable weaponry) than Megalodon...
I think if we are to look at it's teeth, then the closest animal today in terms of similarity is the Great White.
Fair enough, but then the great white shark is supossedly more related to makos than to Megalodon, and their teeth are fairly different- it may have more to do with their main diet (large marine mammals) whereas makos feed mostly on fish.
So it's not impossible that the Megalodon looked very different from the great white yet evolved the same type of teeth via convergent evolution, right?Another idea might be that the Meg was simply too perfect a predator. The only thing that could probably have killed a Meg was a bigger Meg. Pretty much everything in the sea would have been on the menu. Maybe it was a case of nature enforcing her own checks and balances. Predator gets so big and efficient that nature cannot replenish prey species fast enough. Predator dies off or evolves into a smaller species (GWS)
That would be the most awesomest explanation for its demise- it was too formidable for its own good XD
But, I think we are forgetting Leviathan melvillei (yes, I like the old spelling), whose humongous teeth have been found all over the world, not only in Peru, and may have been Megalodon's greatest (and only?) rival. I'm not saying Leviathan was a constant threat to Megalodon (I would even say it was probably the other way around, at least for smaller Leviathans) but I would bet this is one thing that "could probably have killed a Meg". Just look at those teeth, and also, seems that whales stun/kill many of their prey/enemies by simply ramming them with their heads.
Awesome, this thread seems to have started with lots of energy :cool:0 -
Carbon dating on some of the fossil teeth found in Australian waters have given a potential extinction date of between 30,000 to 10,000 years ago. I am too lazy to go upstairs right now but in Great White Shark by Richard Ellis and John McCosker , there is a full chapter devoted to the Megaladon with reference made to the carbon dating of some of the fossil teeth that have been found.
Obviously it is not conclusive, but many now think the 1 million + years date is quite a bit off of the mark.
Carbon dating for marine species is very unreliable, so I wouldn't use it as a measurement for dating Megalodon fossils. If you have a paper on it, I'd love to have a read of it however.0 -
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I thought the recent looking fossils were not held in high esteem among the palaeontological community? I forget where, but I heard they had been more or less discredited.
There were a few quarters who were pretty much saying that it was impossible for them to have been around later than originally thought. Then again how many things were quoted as fact in the past about one animal or another only for what was known to be proven wrong.
From what I remember the carbon dating was done by reputable quarters and the findings were presented by people who were respected in that field.
I know that Richard Ellis was one of the names that thought the findings were more than just plausible, and McCosker agreed with him. When it comes to all things shark (past or present), you would be hard pressed to find two more respected names and two more knowlegable people. If they think the timeline is a very plausible one, then I am willing to give them the benefit of the doubt over paleos who specialize in other fields.Given how cagey Ellis in particular is with regards what gets printed in his books, methinks he was pretty sold on the findings to endorse them.0 -
I'm guessing by that time Megalodon must have been rare, and that's why not many recent teeth are found? Or maybe just not enough teeth have been properly dated...
I agree. I've read that it would have a short, less conical snout than the great white shark or makos as well. Basically it would be more mouth than nose :cool:
Never say neverI have read reports of orcas hunting large bull sperm whales too. They are not to be underestimated. That being said, sperm whales are probably slower (and have much less formidable weaponry) than Megalodon...
Fair enough, but then the great white shark is supossedly more related to makos than to Megalodon, and their teeth are fairly different- it may have more to do with their main diet (large marine mammals) whereas makos feed mostly on fish.
So it's not impossible that the Megalodon looked very different from the great white yet evolved the same type of teeth via convergent evolution, right?
That would be the most awesomest explanation for its demise- it was too formidable for its own good XD
But, I think we are forgetting Leviathan melvillei (yes, I like the old spelling), whose humongous teeth have been found all over the world, not only in Peru, and may have been Megalodon's greatest (and only?) rival. I'm not saying Leviathan was a constant threat to Megalodon (I would even say it was probably the other way around, at least for smaller Leviathans) but I would bet this is one thing that "could probably have killed a Meg". Just look at those teeth, and also, seems that whales stun/kill many of their prey/enemies by simply ramming them with their heads.
Awesome, this thread seems to have started with lots of energy :cool:
Yeah you are correct to say that the Great white has more in common in many ways to extinct mako type sharks than the Meg, but then again we know more about that line of Mako than the Meg at present so who knows what finds may turn up at a future date.:D
When I said that I thought the Meg would have been more like a GW on steroids, I was saying that against the line of thought that it was a slimmer more streamlined creature, something that Galv brought up. As I already said the lower end of the size estimates for it paint a picture for me of quite a heavily built and powerful creature. I think that if we could imagine a Great white as a dairy cow, then the Meg would be something more akin to a Bison. If that makes sense to folk.:D
As for Orca attacking Bull Sperm whales, I think the only documented cases were in fact those when a Bull attacked an Orca pod that was harassing the cow or calf sperm whale. In some of those case the Orca went to make a fight of it, but I think there is nothing on record of an Orca pod attacking a healthy fully grown Bull.
Having said that I think the Killer Whale is an amazing animal, and one that gave me one of my best (and most terrifying) free diving experiences when I came literally face to face with one that decided to investigate me some years ago. It was terrifying because I did not realise they were there, and by the time I did one was coming towards me at pace to check me out. I have been under water with a lot of big animals including GWs, but I don't think anything has quite matched that face to face experience for me as of yet.
Ahh good old Leviathan melvillei:D Been a while since it last appeared on Boards. Awesome creature in it's own right.
You mention whales ramming, and it is something that some whales and most dolphin (including the Killer Whale) will do. But it is also something that a huge heavy, powerful shark might do. Especially one that might have resembled a locomotive with one end just teeth.:)0 -
Carbon dating for marine species is very unreliable, so I wouldn't use it as a measurement for dating Megalodon fossils. If you have a paper on it, I'd love to have a read of it however.
Indeed it is unreliable to a degree, which is why any estimate has to be seen as a potential time stamp rather than a certainty. It also makes a case against those that claim the species could not have been around much later than originally thought as just as much doubt can be applied to the carbon dating done to get the original estimates for the Meg.
If some paleos want to come out and discredit the newer estimates by saying carbon dating is not reliable, then they cannot use carbon dating to back up their arguements for the 1-2 million year arguement as they have already cast doubt on carbon dating.
I don't have a link to any paper to hand, but the book I mentioned does reference that time line and both Ellis and McCosker are backing that timeline, and as I said in my earlier post I don't think there is anyone better than those two when it comes to all things Shark, well at least until someone else comes along and proves something new..
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As for Orca attacking Bull Sperm whales, I think the only documented cases were in fact those when a Bull attacked an Orca pod that was harassing the cow or calf sperm whale. In some of those case the Orca went to make a fight of it, but I think there is nothing on record of an Orca pod attacking a healthy fully grown Bull.
I have a book that tells of an orca pod attacking a group of sperm whales including a large male, and actually it states that the one whale they ended up feeding on was the bull.
But the book doesn´t give any references of this case, so I'm gonna take advantage of the fact that I know the author of the book and I'm gonna ask him what his sources are.Having said that I think the Killer Whale is an amazing animal, and one that gave me one of my best (and most terrifying) free diving experiences when I came literally face to face with one that decided to investigate me some years ago. It was terrifying because I did not realise they were there, and by the time I did one was coming towards me at pace to check me out. I have been under water with a lot of big animals including GWs, but I don't think anything has quite matched that face to face experience for me as of yet.
You lucky bastard. Even though I'm somewhat scared of cetaceans (I'm more calm around sharks!), I still envy those experiences XD We could have an interesting discussion about orcas and how they don´t seem to attack humans in the wild but... no, we're talking about Megalodon :pac:You mention whales ramming, and it is something that some whales and most dolphin (including the Killer Whale) will do. But it is also something that a huge heavy, powerful shark might do. Especially one that might have resembled a locomotive with one end just teeth.:)
By this you mean Megalodon could have rammed, or modern day sharks do? I know they often bump their prey with their heads before the initial bite but I thought this was only for testing the target before the actual bite...0 -
I have a book that tells of an orca pod attacking a group of sperm whales including a large male, and actually it states that the one whale they ended up feeding on was the bull.
But the book doesn´t give any references of this case, so I'm gonna take advantage of the fact that I know the author of the book and I'm gonna ask him what his sources are.
You lucky bastard. Even though I'm somewhat scared of cetaceans (I'm more calm around sharks!), I still envy those experiences XD We could have an interesting discussion about orcas and how they don´t seem to attack humans in the wild but... no, we're talking about Megalodon :pac:
By this you mean Megalodon could have rammed, or modern day sharks do? I know they often bump their prey with their heads before the initial bite but I thought this was only for testing the target before the actual bite...
I meant that Meg could have been a ram attacker, as in using impact to drive it's bite in even further. Would actually make a bit of sense if we were to imagine the Meg as having a much shorter snout that a GW.
Think about how a GW can attack using a similar method. It often hits like a train and takes a massive bite in doing so. Now scale up that attack so that it reflected a 20 ton or more shark with a blunter head.
As for a good chat about Orca and other marine life, I am sure we could. I have been in the water with a hell of a lot of animals at this stage of my life, and all over the globe. I'm actually a bit like you in that I am calmer around sharks. I actually find them a little easier to "read" when under the water with most species having little tells to let you know when to stay away. Now of course this is not a flawless way to avoid being eaten, but I have found certain species of dolphin much harder to read and have had more scary moments involving warm blooded animals in the sea than I have with cold blooded ones. It's always fun when you are underwater and something bigger than you turns up when you were not expecting itHell it happens to me in Irish waters let alone foreign climes.
Would be very interested to find out what you hear about the Orca feeding on the Bull. I have read a report where the Orca pod attacked the cows and calves and a Bull came to defend them which caused a battle between the pod and the bull, but I have never heard of a case where the Bull was singled out over cows and calves and killed.0 -
Would be very interested to find out what you hear about the Orca feeding on the Bull. I have read a report where the Orca pod attacked the cows and calves and a Bull came to defend them which caused a battle between the pod and the bull, but I have never heard of a case where the Bull was singled out over cows and calves and killed.
Could it possibly be the same case? Maybe if the bull came to defend the pod, and the orcas fought him, they ended up beating him and feeding on him instead?
I'll let you know what I find out. :cool:0 -
Could it possibly be the same case? Maybe if the bull came to defend the pod, and the orcas fought him, they ended up beating him and feeding on him instead?
I'll let you know what I find out. :cool:
Quite possibly the same case or one very much like it.
As a bit of an aside on Orca and GWs. I have spent quite a bit of time near the Farallon islands over the years, and the place is normally a hot spot for GWs, with some massive specimen on show for most of the year, but at roughly the same time each year a large number of Orca come in and the GWs head elsewhere. Then sometime later the GWs return and the Orca are gone.
Bloody cold water there, but an amazing spot to see some huge shark along with whale, dolphin, seal and many other forms of marine life along with seabirds.
Susan Casey wrote a book called the Devil's Teeth which goes into some detail about the sharks in that area and the obsession many feel that drives them to try and look at those sharks. Great book (audio version on itunes is even better as Susan Casey herself narrates it) as it really hit the nail on the head for me in terms of my own urges to see certain animals over and over.0 -
Quite possibly the same case or one very much like it.
As a bit of an aside on Orca and GWs. I have spent quite a bit of time near the Farallon islands over the years, and the place is normally a hot spot for GWs, with some massive specimen on show for most of the year, but at roughly the same time each year a large number of Orca come in and the GWs head elsewhere. Then sometime later the GWs return and the Orca are gone.
Bloody cold water there, but an amazing spot to see some huge shark along with whale, dolphin, seal and many other forms of marine life along with seabirds.
Susan Casey wrote a book called the Devil's Teeth which goes into some detail about the sharks in that area and the obsession many feel that drives them to try and look at those sharks. Great book (audio version on itunes is even better as Susan Casey herself narrates it) as it really hit the nail on the head for me in terms of my own urges to see certain animals over and over.
Devil's Teeth is among the books in my Amazon list... just waiting for me to have enough money to order them XD
Any other books on sharks you recommend? (Hope Galvasean doesn´t think this is too off-topic XD)0 -
Galvasean is just happy to see a thread make it to page 2....0
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Loving this thread, thanks for starting it OP!
Here are a couple of shots of my Meg tooth fossil:
Front
Rear0 -
Indeed it is unreliable to a degree
It's completely unreliable, in that - it cannot and should not be used to date marine species. Have a read about the reservoir effect.If some paleos want to come out and discredit the newer estimates by saying carbon dating is not reliable, then they cannot use carbon dating to back up their arguements for the 1-2 million year arguement as they have already cast doubt on carbon dating.
Carbon-dating is only accurate up to 58,000 years, so it would be never used to date marine fossils beyond that age. I'm not sure exactly what radiometric dating method they used to date previous megalodon fossils, but it certainly wasn't Carbon-14 dating.0 -
Devil's Teeth is among the books in my Amazon list... just waiting for me to have enough money to order them XD
Any other books on sharks you recommend? (Hope Galvasean doesn´t think this is too off-topic XD)
Get Great White Shark by Richard Ellis and McCosker. Pretty much the definitive book on Great Whites. Easily the most read book in my marine life collection.
If you can, do what I mentioned earlier with regards to Devil's Teeth and get the audio book that is narrated by the author. Her passion for the topic really comes through.
Shark Life: True Stories about Sharks & the Sea by the late Peter Benchley (yep that Peter Benchley) is worth the purchase as well. Nowhere near as good as the Richard Ellis book, but still a good read as it takes in more species than Ellis' book.0 -
Loving this thread, thanks for starting it OP!
Here are a couple of shots of my Meg tooth fossil:
Front
Rear
What always amazes me (and it really should not amaze me as it is a pretty basic thing) is that pretty much every megaladon tooth fossil that is in circulation has little to none of the original tooth left in it.0 -
Get Great White Shark by Richard Ellis and McCosker. Pretty much the definitive book on Great Whites. Easily the most read book in my marine life collection.
If you can, do what I mentioned earlier with regards to Devil's Teeth and get the audio book that is narrated by the author. Her passion for the topic really comes through.
Shark Life: True Stories about Sharks & the Sea by the late Peter Benchley (yep that Peter Benchley) is worth the purchase as well. Nowhere near as good as the Richard Ellis book, but still a good read as it takes in more species than Ellis' book.
Thanks a lot! I'll check em out!
How do you add a pic from your drive into a post? I want to show off my own Megalodon teeth (from juveniles but still XD)0 -
The talk about Leviathan m. being a rival to the Meg is not strictly true I would have thought. An enemy though is very plausible. Especially as most whale species live in pods (or whatever else you can call them) 1 Leviathan might not have been overly troublesome for a meg (it may have been but I don't know), but half a dozen of them would have turned the meg into a giant pile of sushi.
(Just my own opinion, feel free to disagree.)0 -
The talk about Leviathan m. being a rival to the Meg is not strictly true I would have thought. An enemy though is very plausible. Especially as most whale species live in pods (or whatever else you can call them) 1 Leviathan might not have been overly troublesome for a meg (it may have been but I don't know), but half a dozen of them would have turned the meg into a giant pile of sushi.
(Just my own opinion, feel free to disagree.)
I think it's easy to underestimate cetaceans... I think a fully grown Leviathan may have been a dangerous foe to a Megalodon. It is a shame that we don´t have more Leviathan fossils- to date we have no idea if it was solitary or not, or if females and young traveled in pods and males lived apart, like modern day sperm whales...0 -
Interesting point Rubecula, in Jurassic Fight Club they reckon a pod of Brygmophyseter were more than a match for megalodon. Now, they were only 7 meters long, so the 'Leviathan' would have been a much harsher enemy for Meg had they also moved in pods.
*Not that I believe a word JFC say...0 -
Interesting point Rubecula, in Jurassic Fight Club they reckon a pod of Brygmophyseter were more than a match for megalodon. Now, they were only 7 meters long, so the 'Leviathan' would have been a much harsher enemy for Meg had they also moved in pods.
*Not that I believe a word JFC say...
I think they were desperate to find something that could face Megalodon- I'm sure if the show had been made more recently they would have used Leviathan instead. :pac:0 -
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Apparently they exaggerated Brygmophyseter's size too, from 7 to twelve meters in length. When all else fails... make something up!0
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