Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Science https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Mysterious ancient event Almost destroyed sharks

Mysterious ancient event Almost destroyed sharks

“Sharks barely survived a mysterious and undiscovered catastrophe 19 million years ago that nearly wiped them off the planet.” New paper in Science exposes the unexpected discovery, reports Gizmodo. Researchers used soil samples from the ocean floor to map shark populations over the eons when they found a sharp decline in the so-called Early Miocene period. Sudden is actually an understatement. Based on observations of shark scales or sharks and other evidence, the researchers found that the global shark population has declined by 90% and shark diversity has declined by 70% in a relatively short period of 1

00,000 years. National Geographic. In fact, sharks have never regained their former numbers or diversity, he notes New York Times.

“Sharks are screaming, ‘Something really big has happened here,'” said lead author Elizabeth Siebert of Yale University. Geographically. “Sharks have an evolutionary history of 400 million years; they have been for a long time; they have seen a lot. And is there anything that can knock out 90% of them? “It is particularly puzzling that the mass extinction does not coincide with any known cataclysm that has hit the planet. However, the studied nuts in the sediments suggest that whatever happened is indeed a global event, paleontologists say. In contrast, shark populations declined by a relatively modest 30% during extinction, which wiped out dinosaurs 66 million years ago. (Meanwhile, the current shark population has declined since 1970.)

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