The rise and fall of the seas may have a more lethal toll on Earth’s life than asteroids and supervolcanoes, according to a new study.

Over the past 540 million years, every increase in the rate of extinctions—including the five so-called mass extinctions—has been linked to environmental changes wrought by changing sea levels, the study says.

Only some mass-extinction events, though, have been clearly linked to space-rock impacts and supervolcano eruptions—blasts many times greater than any in recorded times—researchers say.

“To me, that is pretty striking,” study leader Shanan Peters, a geologist at the University of Wisconsin, Madison, said.

The research may be especially relevant today, as what some scientists are calling the sixth mass extinction may already be underway, perhaps due to global warming. 

Source: National Geographic