Ancient giant shark tooth goes missing in Australia

March 13, 2018

The well-preserved tooth is an estimated 2-2.5 million years old and belonged to a Megalodon, regarded as one of the largest and most powerful fish to have ever lived

A giant fossilised tooth from a prehistoric shark has gone missing from a supposedly secret location at a remote Australian World Heritage site, and wildlife officials want it back.

The well-preserved tooth, which could be valuable to collectors, is an estimated 2-2.5 million years old and belonged to a Megalodon, regarded as one of the largest and most powerful fish to have ever lived.

"It had quite defined features on it, so you could see the serrated edge of the shark's tooth, it was probably one of the better specimens we knew of," said Arvid Hogstrom from Parks and Wildlife in Western Australia.

One of just a few Megalodon specimens in the Ningaloo Coast World Heritage Area, "very few people" knew of its location, he added, without elaborating on exactly how many.

"It is not something someone would have stumbled across and they have been required to put a bit of effort in to get it out of the rock as well," he said.

"We presume... an amateur collector (has taken it) or someone that just wants to have a fossil sitting on their mantelpiece."

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Megalodon Ancestor: Fossil Teeth Link Beast to Earth’s Largest Shark

By Laura Geggel, Senior Writer | January 8, 2018 07:33am ET

It took nearly 40 years, but researchers have finally collected enough fossil teeth in Alabama to properly identify a previously unknown species of ancient shark — one that was a possible ancestor of megalodon, the largest shark to ever exist.

The newly identified mega-toothed shark lived about 83 million years ago, during the dinosaur age. Its largest tooth discovered so far measures about 1 inch (2.7 centimeters) long, which is substantially smaller than the 7-inch-long (17.7 cm) teeth sported by megalodon (Carcharocles megalodon), the researchers said in a new study.

"Over time, the sharks in the megalodon line acquire [tooth] serrations, lose their cusplets (the little 'fangs' on the sides of the main cusp) and grow to enormous sizes," said study lead researcher Jun Ebersole, director of collections at the McWane Science Center in Birmingham, Alabama. The newfound shark is an early member of this family, so its teeth are small and unserrated, with up to two pairs of cusplets, he said. [Aahhhhh! 5 Scary Shark Myths Busted]

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Megalodon's Demise: Why Earth's Largest Shark Went Extinct

By Jen Viegas, Seeker | January 13, 2017 11:41am ET 

Megalodon, the largest known shark that ever lived, had a taste for small whales and it went extinct when populations of their favorite prey collapsed as the Pliocene Epoch (5.3–2.58 million years ago) drew to a close, new evidence indicates.

The evidence—reported in the journal Palaeogeography, Palaeoclimatology, Palaeoecology—consists of fossilized bones from animals that megalodon devoured. Riddled with the enormous shark's bite marks, the fossils are the first to show exactly what species the megalodon consumed in its diet.

All of the fossils were unearthed at a site called Aguada de Lomas in southern Peru.

Lead author Alberto Collareta of the University of Pisa and his team analyzed the fossils and determined that megalodon, which could grow to over 53 feet long, ate the now-extinct baleen whale Piscobalaena nana and the early seal Piscophoca pacifica. Both animals were still impressive in size, at just under 16.5 feet long, but were presumably easy, nutritious pickings for megalodon.

"What else would you eat but a large marine mammal?" Christina Slager, director of animal care and exhibits for San Francisco's Aquarium of the Bay, told Seeker when told of the new findings.

She said that great white sharks today like to eat seals and sea lions, but will usually only scavenge on whales. Except for the pygmy right whale, all other baleen (filter-feeding) whales today greatly surpass even the biggest great white sharks in size.

Kenshu Shimada, a professor of paleobiology at DePaul University, explained to Seeker that whales have likely become bigger than sharks "due to the evolution of their migration behavior where large body sizes must have helped them to travel long distances and exploit food sources not only along the coasts but also in the middle of the ocean."

He added, "Whether megalodon migrated long distances can only be speculated at the present time."

Uncertainty also exists concerning how megalodon interacted with its whale prey. Collareta and his colleagues admit that "it is virtually impossible to discriminate between active predation and scavenging when dealing with fossil specimens," yet they believe it is possible megalodon actively hunted small-sized whales.

In fact, one of the fossils is a whale skull that the shark bit directly into, going right after the head meat. This and the other bite marks unmistakably were made by megalodon, according to the researchers. One tooth mark alone, they say, measured over 2 inches long.

Such an enormous predator would seem to be invincible, but megalodon was on Earth only from about 23 to 2.58 million years ago.

Slager said that the traditional explanation for the giant shark's disappearance has been climate change.

Read on 

Enormous prehistoric Megalodon teeth wash up on North Carolina shore

OCTOBER 26, 2015

by Savanna Walker

Enormous prehistoric shark teeth have washed up on a North Carolina beach after a storm, and the biggest are million year old Megalodon teeth, which are as large as an adult’s hand. *Shudders*

Starting in October, teeth have been found from Surf City to North Topsail Beach due to stormy weather and high tides. Local beachgoer Denny Bland found one a Megalodon tooth that was almost six inches long—only an inch shorter than the largest ever found.

About these terrifying creatures

Megalodon went extinct about 2.6 million years ago and was the largest shark to ever live at a terrifying 60 feet long. (That’s about three times the size of a great white!) Megalodon continually evolved to grow bigger over its 14-million year existence, but scientists are unsure why this was the case.

"Perhaps something was going on with the productivity and climate that produced that pattern, or with their prey and their competitors that made the species become large," said study co-author Catalina Pimiento from the University of Florida and the Smithsonian Tropical Research Institute in Panama. And while Megalodon’s colossal size may have led to its extinction, while it lived it was a ferocious predator with a jaw three times as strong as a Tyrannosaurus rex.

Read more at

Monster shark 'kept whales in check'

23 October 2014 Last updated at 16:23

By Paul Rincon

Science editor, BBC News website

The extinction of the biggest shark known to science may have triggered whales to grow to their current hefty sizes, a study suggests.

Megalodon, an ancient 14-18m-long predator that resembled a super-sized Great White, may have preyed on primitive baleen whales.

These whales were typically smaller than their counterparts today.

In their paper, the researchers produce what they say is the best estimate yet for the date of Megalodon's extinction.

This date of 2.6 million years ago falls on the border between the Pliocene and Pleistocene epochs. And it was after this point that baleen whales began to grow to their gigantic sizes.

Marine mammals are thought to have constituted an important part of the 50-tonne shark's diet. Though there's no conclusive evidence they fed on baleen whales, their fossils are often found along with Megalodon (Carcharocles megalodon) teeth.

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