Theropods – the family of dinosaurs that included the mighty Tyrannosaurus rex and the smaller Allosaurus – had the largest and most sophisticated brains of any such dinosaur group. But scientists aren’t sure how they used these advanced faculties, whether for hunting or tracking down the next corpse to scavenge.A 2011 study found that if you set loose a group of scavenging T. rex’s in an environment comparable to the Serengeti in Africa, they would struggle to survive. But a new st ...read more

Cats are mysterious creatures. There’s a lot we don’t understand about them. Why do they sleep on our heads? Why do they almost always land on their feet? Why do they love boxes so much? One cat mystery, however, may have been solved. A team of European researchers say they’ve found an answer to the question — how do cats purr — that has vexed science, and owners, for decades.How Do Cats Purr?Cats have an amazing vocal range, from high-pitched yowls and screeches to deep, resonant pu ...read more

Mars looms large in the scientific imagination, as well as in fiction. Of all the worlds of the solar system, it’s the only one Earth-like enough for exploration with Earth-like tools: Its atmosphere is thin and transparent, its surface is dry and cold, and it’s close enough for regular study. From telescope eyepieces, we’ve probed the Red Planet for centuries. And over the past 50 years, we’ve even sent instruments for a closer look.However, in geological terms, that’s just a sliver o ...read more

The routes that our ancestors followed out of Africa have been long debated. But now researchers have uncovered evidence that the so-called northern route — a traverse that took Homo sapiens from the Sinai Peninsula into the Jordan Rift Valley — might have been a particularly viable corridor during the last interglacial period, which persisted from about 129,000 to 71,000 years ago. Sediments unearthed at three sites in southern Jordan suggest that wetland conditions likely persisted there ...read more

Acapulco wasn’t prepared when Hurricane Otis struck as a powerful Category 5 storm on Oct. 25, 2023. The short notice as the storm rapidly intensified over the Pacific Ocean wasn’t the only problem – the Mexican resort city’s buildings weren’t designed to handle anything close to Otis’ 165 mph winds.While Acapulco’s oceanfront high-rises were built to withstand the region’s powerful earthquakes, they had a weakness.Since powerful hurricanes are rare in Acapulco, Mexico’s b ...read more

Have you ever wondered whether the virus that gave you a nasty cold can catch one itself? It may comfort you to know that, yes, viruses can actually get sick. Even better, as karmic justice would have it, the culprits turn out to be other viruses.Viruses can get sick in the sense that their normal function is impaired. When a virus enters a cell, it can either go dormant or start replicating right away. When replicating, the virus essentially commandeers the molecular factory of the cell to mak ...read more

The first primates arrived in the Americas about 56 million years ago and prospered for a time, but it wasn’t to be.They died out some 34 million years ago, after the Eocene-Oligocene extinction event, during which the planet became cooler and drier. Half of all mammal genera died around the globe.But somehow, this set the stage for a lemur-like animal known as Ekgmowechashala to establish itself in the Great Plains of the present-day U.S.Scientists have disputed how to classify the odd-looki ...read more

Colorful bodies painted in vibrant reds or blacks, heads dressed in wigs of human hair, and masks with eyes and mouths wide open, as if still breathing – these were the mummies made by the Chinchorro people.They were among the earliest ancient humans to settle on what’s now the coast of northern Chile and southern Peru. And the mummies are the oldest in the world, predating even the first mummified pharaohs of Ancient Egypt by a couple millennia. But after thousands of years, Chinchorro mumm ...read more

This story was originally published in our Nov/Dec 2023 issue as "Answers in the Ashes" Click here to subscribe to read more stories like this one.Tom Kluge was at home getting ready for work when he got the call from an emergency command center dispatch. It was Nov. 8, 2018, and a wildland fire had been spotted northeast of Pulga, a remote community tucked away in the northern Sierra Nevada mountains about 35 miles from where Kluge was stationed.At the time a fire captain specialist and 16-y ...read more

This story was originally published in our Nov/Dec 2023 issue as "Floating in the Clouds" Click here to subscribe to read more stories like this one.Stepping onto one of the Uros islands in southern Peru can feel like walking on a bouncy castle. Your feet sink a bit into the mushy floor, which trembles slightly when a motorboat speeds past. That’s because this land is actually floating — on the largest lake in South America, located 12,500 feet above sea level in the Andes Mountains.Hundr ...read more