Their teeth would sink down to the bottom of the ocean, where they would likely be fossilized. Megalodon sharks first showed up about 16 million years ago, and they were a dominant predator in the ocean.
Measuring anywhere between 10 to 18 meters 33 to 59 feet , these giant beasts preyed upon anything from fish to dolphins, and even whales! One theory is that they became extinct due to decreasing food sources, and increasing competition for that food.
We could also see megalodons tracking fishing boats and stealing the fish they catch, just like some killer whales do. With ocean temperatures warming up again, megalodons would be thriving and reproducing, resulting in even more of these giant mammals in the water. That would spell trouble for maritime shipping operations, cruise ships, and even beachgoers. Megalodons gave birth in warm, shallow waters, so a nice recreational beach swim could become very dangerous for us.
What would our planet look like if no animals ever went extinct? Scroll down for the quiz! There is an invisible force protecting us, keeping our atmosphere in place. Without it, life on Earth would be over very quickly. Take a deep breath.
We take 23, breaths a day; trying to get oxygen to our brain and cells. Oxygen is essential to our survival. Millions of years ago, the megalodon shark was one of the scariest creatures to ever lurk in our seas. And even before that, the mosasaurs reigned supreme, terrorizing In the time it would take you to order an extra larger everything pizza and have it delivered to your front door you could theoretically jump through that tunnel This is the world million years ago.
The image below is a classic one. It is most likely a basking shark with artistic touches nice legs! This work is U. Videos and images of giant sharks do exist. Many of them are real. The reason is because there are large sharks, similar in size to what megalodon was, that exist today. The average size of a megalodon was around 30 feet see the Megalodon Size Page for cited size information. Other large sharks can reach simlar sizes today. Two of these sharks are the Whale shark and the Basking Shark.
Whale sharks can reach lengths of around 40 feet, which is similar to a Megalodon. But they have a distinctive wide and flat appearance. They are black with white spots on them. However, the other large shark, the basking shark, has been mistaken for megalodon.
Basking sharks inhabit coastal waters and feed on plankton. These docile sharks grow up to 40 feet; similar in size to a megalodon. On the rare occasion when these beautiful creatures are spotted by beachgoers, they can easily be confused with a megalodon by someone with an overactive imagination. Just because a giant shark is sighted doesn't mean it's a prehistoric megalodon, it could very well be one of these amazing basking sharks.
A classic example is shown in the Harpers Weekly image above and another good example is shown below. This amazing photo is of a Basking shark swimming near a beachgoer.
Basking sharks can easily be misidentified as a megalodon by people with overactive imaginations. Image courtesy of candiche.
If a megalodon body washed ashore today, or one was videotaped or photographed swimming around, it would make instant global news and not just news in the conspiracy annals of youtube. This is a popular piece of evidence used. The most recent ones are still over 2 million years old. The origin of "recent megalodon teeth" started in the 's. Megalodon teeth were found in the South Pacific from dredging along deep foot slopes of a fringing reef around New Caledonia.
The enamel on many of these teeth are leeched such that a white color was left, making them slightly resemble a recent tooth. The type of age dating done in the 's was Manganese dioxide dating. The Manganese dioxide dating gave an age range of the sampled teeth to be between 11, and 24, years old.
This type of manganese dioxide dating is now considered invalid, due to the teeth being eroded out of their original formation and re-deposited. Today, modern dating methods indicate the teeth are eroded from a Miocene formation, which is between 23 and 5 million years old. Any source that uses the "evidence" that teeth pulled from the South Pacific are 11, to 24, years old are purposely misleading the reader by using invalid and outdated evidence.
On a side note, these beautiful fossil megalodon teeth use to be dredged from this area by the boatload. In the French pulled the permit for dredging in this area. Today these beautiful New Caledonian fossil megalodon teeth cannot be collected. If a recent megalodon tooth was ever found, Paleontologists and marine Biologists would have a field day publishing new journal articles. These scientific and peer reviewed articles do not exist.
There is no scientific evidence of megalodon evolving into anything else. Evidence suggests it went extinct approximately 3. Let's start this one by looking at megalodon origins. Although the fossil record can be spotty and there are gaps, the fossil record for shark teeth in tertiary deposits is actually nearly complete.
Scientists have a very nice evolutionary history of the megatooth sharks starting way back in the cretaceous with the shark Cretolamna appenticulata. As time goes on, there is a clear fossil record of slight changes in the shark teeth.
The cusps gradually become smaller and dissapear. Cutting edges become serrated, the crown gets broader, and the overall size of the teeth increases over time. Paleontologists assign each change of the megatooth shark into new species, and even genera, until the high mark is reached; Otodus Carcharocles megalodon. Yes, there is debate over exact species names, genera names, and when one morphological form is pronounced enough to be considered a new species.
But everyone does agree, the fossil record is very clear and complete when it comes to the evolutionary history of megalodon. The extinction of megalodon also is clear in the fossil record. Fossils of megalodon are plentiful, but at the mid-end Pliocene, they vanish. This doesn't mean there are not marine Pleistocene formations. There are, and they are plentiful.
They contain an array of marine fauna, including many surviving sharks and surviving whales. They just don't contain megalodon fossils anymore. There are no transitional fossils showing a gradual change of megalodon into something else, there simply are no fossils of megalodon or similar creatures. If megalodon changed into something else, there would be a clear record in these well studied Pleistocene formations.
There is no record, they completely vanish. The only valid conclusion is megalodon became extinct. This shows the evolution of the megalodon, from a small Cretaceous shark to the apex predator of the Pliocene. So yeah, sorry guys, but Megalodon is definitely extinct. In my opinion, a fictional portrayal of Megalodon would probably be better suited to embodying a wider theme about how humans fear and misunderstand sharks as a whole.
Sharks are some of the most fascinating, and long-lived, animals on the planet, dating back over million years. With all that history comes a gold mine for palaeontologists to understand their prehistoric lives swimming, eating and making little sharks. And Megalodon is very much the queen of shark palaeontology, capturing imaginations worldwide and inspiring a huge array of cool research, with a broad cast of scientists studying them Fig.
I hope that this short series has provided some interesting insight into just how much work has gone into learning about this giant shark. Your email address will not be published. Save my name, email, and website in this browser for the next time I comment. Ancient nursery area for the extinct giant shark Megalodon from the Miocene of Panama.
PLoS One 5 , e Insights into young of the year white shark, Carcharodon carcharias , behavior in the Southern California Bight. Fishes 70 , Shark nursery areas: concepts, definition, characterization and assumptions.
Neues Jahrb. Did the giant extinct shark Carcharocles megalodon target small prey? Bite marks on marine mammal remains from the late Miocene of Peru. Geographical distribution patterns of Carcharocles megalodon over time reveal clues about extinction mechanisms.
Climate, critters, and cetaceans: Cenozoic drivers of the evolution of modern whales. Science , , Fallows C, Gallagher A. White sharks Carcharodon carcharias scavenging on whales and its potential role in further shaping the ecology of an apex predator.
PLoS One , 8 , e Elife 3 , e
0コメント