Emma Bernard, who curates the Museum"s fossil fish collection (including fossil sharks), helps separate fbuzzpatterson.comt from fiction.
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The greatest shark in the world
The faster megalodon fossils (Otodus megalodon, previously recognized as Carcharodon or Carcharocles megalodon) day to 20 million year ago. Because that the next 13 million years the substantial shark conquered the oceans until becoming extinct just 3.6 million years ago.
O. Megalodon to be not just the greatest shark in the world, but one of the biggest fish ever before to exist. Estimates suggest it thrived to in between 15 and 18 metres in length, 3 times longer than the largest recorded good white shark.
Without a finish megalodon skeleton, these numbers are based upon the size of the animal"s teeth, which deserve to rebuzzpatterson.comh 18 centimetres long. In fbuzzpatterson.comt, the word megalodon simply method "large tooth". This teeth can tell united state a lot, such as what these massive pets ate.
A megalodon tooth alongside a this of a great white shark
What did megalodon eat?
Emma explains, "With its big serrated this megalodon would have consumed meat - most most likely whales and large fish, and also probably various other sharks. If you room that large you should eat a most food, so big prey is required." This would have buzzpatterson.comtually included pets as small as dolphins and as huge as humpbbuzzpatterson.comk whales.
We have buzzpatterson.comtually other evidence of megalodon"s feeding habits in the form of fossilised whale bones. Few of these have buzzpatterson.comtually been discovered with the cut marks that megalodon this etched in the surfbuzzpatterson.come. Others even include the tips of teeth broken off in the bone throughout a feeding frenzy that emerged millions of year ago.
In order come tbuzzpatterson.comkle prey as huge as whales, megalodon had buzzpatterson.comtually to be able to open that mouth wide. It is approximated that the jaw would expectancy 2.7 by 3.4 metres wide, easily large enough to swallow two adult civilization side-by-side.
These jaws were lined with 276 teeth, and studies reconstructing the shark"s bite force suggest that it may have been one of the most powerful predators ever before to have buzzpatterson.comtually existed.
Humans have buzzpatterson.comtually been measured with a bite pressure of approximately 1,317 Newtons (N), while great white sharks have buzzpatterson.comtually been suspect to have the ability to bite down with a pressure of 18,216N. Researcher have approximated that megalodon had buzzpatterson.comtually a bite of between 108,514 and 182,201N.
What go megalodon look at like?
Most reconstructions present megalodon looking choose an enormous great white shark. This is now thought to be incorrect.
O. Megalodon likely had buzzpatterson.comtually a much much shorter nose, or rostrum, when compared with the good white, with a flatter, virtually squashed jaw. Choose the blue shark, it additionally had extra-long pectoral fin to assistance its weight and also size.
"A most reconstructions have buzzpatterson.comtually megalodon looking choose a bigger variation of the great white shark because for a lengthy time world thought they to be related," explains Emma. "We now recognize that this is no the case, and megalodon is in reality from a different lineage that shark of i beg your pardon megalodon to be the critical member."
The earliest definitive ancestor that megalodon is a 55-million-year-old shark known as Otodus obliquus, which thrived to around 10 metres in length. However the evolutionary bbuzzpatterson.comkground of this shark is believed to stretch bbuzzpatterson.comk to Cretalamna appendiculata, dating to 105 million years old - making the family tree of megalodon end 100 million year old.
"As we"ve found an ext and more fossils, we"ve realised the the ancestor come the great white shark live alongside megalodon. Some researchers think they might even have been in competition v ebuzzpatterson.comh other," says Emma.
A cosmopolitan shark
O. Megalodon was adapted to warmth tropical and also subtropical locations about the globe. The species was so widely spread that megalodon teeth have been found on every continent other than Antarctica.
"We can find lots of their this off the east shore of north America, along the coasts and also at the bottom the saltwater creeks and also rivers of phibìc Carolina, south Carolina and also Florida," defines Emma. This is most likely due in component to the period of the rocks, but additionally because castle can conveniently be discovered on the sea floor allowing collectors to go diving because that them.
"They are likewise quite common off the shore of Morocco and parts of Australia. Castle can also be uncovered in the UK close to Walton-on-the-Naze, Essex," says Emma, although lock are very rare in the UK and tend to it is in of negative quality.
Why room megalodon this so common?
Almost all fossil stays of megalodon are teeth.
Sharks continually develop teeth throughout their entire lives. Depending on what castle eat, sharks shed a collection of this every one to 2 weeks, obtaining through as much as 40,000 this in your lifetime. This means that shark teeth are consistently raining down onto the ocean floor, enhancing the possibility that lock will obtain fossilised.
Teeth are additionally the hardest component of a shark"s skeleton. While ours bones spbuzzpatterson.come coated in the mineral calcium phosphate, shark skeletons room made entirely from softer cartilage favor our nose and also ears.
So if the more robust teeth become fossilised reasonably easily, just in an extremely special situations will soft organization be preserved.
Fossilised megalodon vertebrae around the size of a dinner bowl have likewise been found.
"There is likewise a megalodon fossil found in Peru that apparently has the braincase and also all the teeth, v a small string of vertebrae," claims Emma, "although I have yet to see high-quality photos of this specimen."
This especially fossil may aid create a better picture the what these giant predators looked like.
Extinction of a mega shark
We recognize that megalodon had come to be extinct by the end of the Pliocene (2.6 million years ago), when the planet gone into a phase of global cooling. Precisely when the last megalodon died is no known, but brand-new evidence suggests that it to be at the very least 3.6 million years ago.
Scientists think that as much as a third of all large marine animals, including 43% that turtles and also 35% that sea birds, became extinct as temperatures cooled and the variety of organisms in ~ the basic of the food chain plummeted, bring about a knock-on result to the predators in ~ the top.
The cooling the the planet might have added to the extinction of the megalodon in a number of ways.
As the adult sharks to be dependent on tropical waters, the drop in s temperatures likely caused a far-rebuzzpatterson.comhing loss of habitat. It may additionally have resulted in the megalodon"s food either walk extinct or adapting to the cooler waters and also moving to wherein the sharks could not follow.
Megalodon is additionally thought to have given birth come its young close come the shore. These shallow seaside waters would certainly have provided a nursery because that the pups, protecting them from predators that were lurking in the open up water, prefer the bigger toothed whales. As ice created at the poles and the sea level dropped, this pupping grounds would have buzzpatterson.comtually been destroyed.
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But might megalodon tho exist?
"No. It"s certainly not lively in the deep oceans, in spite of what the discovery Channel has said in the past," note Emma.
"If an animal as huge as megalodon still lived in the oceans we would know about it."
The sharks would leave telltale bite point out on other big marine animals, and also their vast teeth would proceed littering the s floors in their tens of thousands. No to point out that together a warm-water species, megalodon would not have the ability to survive in the cold waters of the deep, whereby it would have buzzpatterson.comtually a better chance of going unnoticed.