It is impossible to believe that they were about to go away completely. It was millions of years ago. It is not yet known what the cause could be. Research into its fossils gave the clue to science. Even an approximate date. Sharks almost disappeared 19 million years ago.
To the limit
“It’s a big secret. Sharks have been around for 400 million years. You have gone through hell and back. And yet this event killed 90% of them “, cube Elisabeth Siber. She is a paleobiologist and oceanographer at Yale University. She is also the author of the study.
The discovery came almost by accident. Sibert is dedicated to researching microfossils from fish teeth and shark scales. He began recording the abundance of fish and sharks over 85 million years.
“We saw a sudden decline in the shark population about 19 million years ago. We knew we had to investigate more », divided the scientific.
The number of deaths was enormous. Twice as many sharks killed during the Cretaceous Paleogenesis mass extinction. It was when an asteroid collided with the earth. It wiped out 75% of the plant and animal species on our planet.
sensitive to extinction
The reason the sharks almost disappeared is unknown. “This interval is not known for any major changes in the history of the earth. But it has completely changed the nature of what it means to be an open ocean predator, ”emphasized Sibert.
It appears to have occurred within an interval of less than 100,000 years. The diversity of sharks in the world’s oceans has never been the same. Many species of the open oceans disappeared completely. The coastal sharks were a little more lucky, say the researchers. The lines that exist today are mainly from these survivors.
“Sharks seem to have difficulty recovering from sudden extinction events. Unfortunately we are now entering another », stressed.