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In a new study published today in the journal Science, researchers say they have confirmed that eruptions large enough to bury the U.S. under 300 feet (91 meters) of lava occurred at the same time that vast numbers of plant and animal species disappeared from the fossil record. About 201 million years ago, tectonic forces started ripping the supercontinent known as Pangaea apart, said Terrence Blackburn, a geologist at the Carnegie Institution for Science in Washington, D.C., and lead author of the study. The underlying mantle rock melted, generating these large eruptions, he added. The rift, which eventually created the Atlantic Ocean basin, happened between sections of Pangaea that would go on to become North America and Africa. (Read about how Pangaea formed.)

by using a rare mineral called zircon, found in igneous rocks like basalts, the researchers were able to narrow down their margin of error to 20,000 to 30,000 years—pegging the initial eruptions to just before the mass extinction event. “Zircon is a perfect time capsule for dating those rocks,” said Blackburn. When the mineral crystallizes, it incorporates uranium, which decays over a known time with respect to the element lead. By measuring the ratio of uranium to lead in our samples, we can determine the age of those crystals, he explained.

There is evidence that the initial volcanic eruptions doubled the amount of the carbon dioxide in the atmosphere, which led to increased global temperatures and ocean acidification, he noted. This happened quickly, which probably didn’t give organisms at the time much of a chance to adjust to the changes.

disproves previous theories that Africa’s dinosaur fauna existed in isolation

Its 2013 discovery marks the most complete fossil recovered of any mainland African land vertebrate.

This landmark discovery provides scientists with yet more intriguing geological and paleontological information about what the world was like when dinosaurs roamed the earth

the most striking feature of this early age of mammals is that it was almost unbelievably hot, so hot that around 50 million years ago there were crocodiles, palm trees, and sand tiger sharks in the Arctic Circle. On the other side of the blue-green orb, in waters that today would surround Antarctica, sea-surface temperatures might have topped an unthinkable 86 degrees Fahrenheit, with near-tropical forests on Antarctica itself. There were perhaps even sprawling, febrile dead zones spanning the tropics, too hot even for animal or plant life of any sort.

This is what you get in an ancient atmosphere with around 1,000 parts per million (ppm) of carbon dioxide. If this number sounds familiar, 1,000 ppm of CO2 is around what humanity is on pace to reach by the end of this century. That should be mildly concerning.

“You put more CO2 in the atmosphere and you get more warming, that’s just super-simple physics that we figured out in the 19th century,” says David Naafs, an organic geochemist at the University of Bristol. “But exactly how much it will warm by the end of the century, we don’t know. Based on our research of these ancient climates, though, it’s probably more than we thought.”

An analysis of clam shells and volcanic rocks from an Italian cave shows that Neanderthals collected shells and pumice from beaches. And due to specific indicators on some of the shells, the researchers also believe Neanderthals waded and dove into the ocean to retrieve shells, meaning they may have been able to swim.

It's fortunate that the shells, as well as the volcanic rock called pumice, were retrieved from the cave and stored at the Italian Institute of Human Paleontology because the cave itself is no longer accessible. Blasting for coastal highway construction buried the cave in the early 1970s.

Shell tools for Neanderthals are rare, and only a few examples of them have been discovered. The majority of tools associated with Neanderthals involve stone spear tips and stone hammers. But there was even less evidence prior to this study that Neanderthals living in Western Europe dove underwater. The study published Wednesday in the journal PLOS.