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Scientists have spent six years determining age of more than 6,000 marine fossils

The findings reveal that many Antarctic creatures died off rapidly 66 million years ago

CNN  — 

When a catastrophic asteroid hit the planet 66 million years ago, scientists believed that creatures in what we now call the South Pole fared pretty well.

But a new analysis suggests that the dinosaur-killing asteroid also annihilated many marine animals in Antarctica.

Scientists at the University of Leeds and the British Antarctic Survey on Seymour Island in the Antarctic Peninsula recently completed testing to determine the age of more than 6,000 marine fossils. They dated from 65 to 69 million years ago – meaning the creatures died around the same time a powerful asteroid struck Earth.

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The research, published in the journal of Nature Communications on Thursday, is giving scientists more insight into one of the greatest mass extinctions on the planet.

This is the first study to argue that the mass die-off that happened at the end of the Cretaceous Period was as rapid and devastating not only around the world, but also at the Earth’s polar regions, according to a statement by the University of Leeds.

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Originally, scientists believed that animals in the polar regions were far enough away from the source of the mass extinction to be harmed.

However, new data reveals there was about a 70% reduction of the animal population in Antarctica 66 million years ago, meaning the deaths of these creatures was sudden and widespread.

“Our research essentially shows that one day everything was fine – the Antarctic had a thriving and diverse marine community – and the next, it wasn’t,” said James Witts, lead author of the study and a doctorate student at the University of Leeds.

“Clearly, a very sudden and catastrophic event had occurred on Earth,” he said.

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In addition, the new fossil evidence solidifies the case that the dinosaurs died because of an asteroid plunging into the Gulf of Mexico, rather than environmental changes due to volcanic activity.

“This is the strongest evidence from fossils that the main driver of this extinction event was the after-effects of a huge asteroid impact, rather than a slower decline caused by natural changes to the climate or by severe volcanism stressing global environments,” Witts said.

The marine fossil collection that was analyzed is the largest to ever be discovered anywhere in the world, according to the University of Leeds. It took researchers six years to date the collection.

These fossils include animals both big and small, ranging from clams on the sea floor to large creatures that lived on the ocean’s surface.

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One of these large marine creatures that scientists were able to date was the giant reptile Mosasaurus, one of the monstrous creatures that was featured in the 2015 science fiction thriller “Jurassic World.”

Since marine fossils are so abundant and provide a robust span of data, the new findings put up a good argument against previous studies suggesting dinosaurs died off slowly, scientists said.