Indholdsfortegnelse for May 2021 i Discover

Every 26 seconds, the Earth shakes. Not a lot — certainly not enough that you’d feel it — but just enough that seismologists on multiple continents get a measurable little blip on their detectors. Though this pulse has been observed for decades, researchers don’t agree on what’s causing it. The pulse — or microseism, in geologist lingo — was first documented in the early 1960s by researcher Jack Oliver at the Lamont Geological Observatory (now known as the Lamont-Doherty Earth Observatory). Oliver figured out that the pulse was coming from somewhere “in the southern or equatorial Atlantic Ocean,” and that it was stronger in the Northern Hemisphere’s summer months. In 1980, Gary Holcomb, a geologist with the U.S. Geological Survey, used new tech to look at the microseism: digital seismometers.…

I was called to see Albert, a 35-year-old man, while he was an inpatient at our hospital. Albert had experienced a bout of hematemesis (vomiting blood) and had been admitted to determine the cause. Although dramatic in nature, hematemesis is a common complaint that we gastroenterologists are trained to evaluate and treat. Most patients have garden-variety problems, such as stomach ulcers or esophagitis (inflammation in the esophagus from acid reflux), that can lead to hematemesis; these troubles are generally easily managed. But not this time. Albert told me that he had been feeling poorly for several months, with symptoms that seemed to come and go. He often experienced severe left-sided back pain that would come on out of the blue, leave him in agony for a few days, and then…

To artists inspired by what they see in nature, volcanic sunsets are the holy grail of light and color. They transform placid sunsets and post-twilight glows into vibrant bloodbaths of spectral radiance. Yet I’m not writing this to hang on the wall another volcanically inspired sunset painting for us to ponder. Rather, I want to introduce to observers a subtle and little-known daytime phenomenon linked to volcanic activity. It may have, in part, inspired 19th-century Post-Impressionist French artist Georges Seurat (1859–1891) in his attempt to reform Impressionism and illuminate the world with a new form of art: his own version of optical blending of color, called Pointillism. THE SKY AS ART A number of 19th-century artists re-created volcanic sunsets in their paintings. Most touted are the works of English landscape…

You may recognize this water-and-wind-carved Navajo sandstone. Countless humans first saw it in 2009, when Microsoft featured The Wave on desktop wallpaper for Windows 7. Then in 2010 came Instagram, where you now can find thousands of hashtagged and geo-tagged images from this remote spot near the Arizona-Utah border. That’s how a far-flung site, known only by locals and a handful of adventurous souls, can catapult into fame. Social media has repeated this effect on many natural spaces around the globe, often sparking overtourism — when excessive traffic can cause site degradation. The Wave has historically avoided that with a strict permit system managed by the U.S. Bureau of Land Management. For decades, just 20 visitors per day have been allowed in this Coyote Buttes North section of the Paria…

ON A COLLISION COURSE (“Is the Universe Infinite?”, Dec 2020) In the article is this statement: “Soon they learned the universe was expanding, too, with galaxies retreating from each other at ever-accelerating speeds.” If this is correct, there can be no collisions between galaxies. But then how does one explain spiral galaxies, the origins of which are explained by the collision of two or more galaxies? James AdieEnterprise, Ala. Author Eric Betz responds: For brevity’s sake, we omitted a detail pertinent to your question. Galaxies in general are retreating from each other, or red-shifted. This was first established observationally by Vesto Slipher and Edwin Hubble, and it’s been confirmed by repeated observations over the past century. However, from our local perspective, a handful of galaxies, like Andromeda, are actually blue-shifted,…

Hiking across Vancouver Island’s Mount Washington, marmot keeper Jordyn Alger is perplexed. “I’ve never not seen a marmot on a walk here before,” she says. Despite her radio-tracking equipment, she’s come up short this hot July afternoon. But as Alger speaks, as if to reward her optimism, a tagged wild marmot appears on a log, eyeing us. The consistency of her sightings reveals an exceptionally effective program of rehabilitation, bringing critically endangered Vancouver Island marmots (Marmota vancouverensis) back from near extinction. The species is distinguished from the other five North American marmot species — and 14 more worldwide — by its dark brown fur. Landscape changes, often linked to trees encroaching on their preferred open spaces, on Vancouver Island throughout the 20th century fragmented the marmots’ mountain habitat, leaving populations…

Baking soda, or sodium bicarbonate, leavens your baked goods because of the chemical reaction it undergoes when mixed with acidic ingredients. Baking powder, on the other hand, is a mix of baking soda, an accompanying acid and a buffering agent. They can’t be used interchangeably unless you’re prepared to do some extra chemistry — like adding an acid, like vinegar, in just the right amounts to activate your baking soda when the recipe calls for powder. And since baking powder packs extra ingredients into the formula, recipes tend to call for larger volumes; putting an identical amount of baking soda in a recipe that calls for powder will ruin your dessert, at best imparting a salty flavor, at worst, a soapy one. It’s safest just to wait until you can…

I’m trying to work but my heart is pounding. I’m in my daughter’s bedroom, the only air-conditioned room in our house. Outside, the French summer roasts at 109 degrees Fahrenheit. But it’s not just the outdoor heat that makes me feel light-headed. I’m reading research papers on climate change with titles like “Accelerating Extinction Risk” and “Accelerated Dryland Expansion.” Everything seems to be accelerating, my pulse included. Thoughts race, too: How bad is it, really? Are we all doomed? Should I start homeschooling my daughter in martial arts, shooting and forest gathering? Should I get a Xanax — or stay true to my Polish roots and just drink some vodka? Scientists already have several terms for what I’m experiencing. Some call it climate anxiety. Others call it pre-traumatic stress disorder…

In Werner Herzog’s latest film, Fireball: Visitors From Darker Worlds, you’ll find no diagrams, no green screen backdrops, no points where the narrator stops to define terms. It’s not your typical science documentary. Of course, you wouldn’t expect that approach from Herzog anyway. The prolific German film and opera director has created Grizzly Man, Cave of Forgotten Dreams, Happy People: A Year in the Taiga and roughly 70 other films (fictional and documentary) over the past 50 years. He also made an acting appearance in The Mandalorian series — even though he’s never watched Star Wars. Most of his work, in one way or another, explores the recesses of human nature, often in the natural world. Herzog teamed up with volcanologist Clive Oppenheimer for a second time to make Fireball,…

Lou Barbe wouldn’t call himself an avid gamer. As an ecologist at the Université de Rennes in France, he spends most of his time with plants. But one game has captured his imagination since childhood: StarCraft, the popular online strategy franchise in which players accrue resources and construct armies of alien fighters to wage war across extraterrestrial landscapes. “I’m not at all a very good player,” says Barbe. “But I understand what’s going on.” While playing StarCraft II — the latest version of the game — a few years ago, Barbe realized that amid all the explosions and lasers, something else was happening. StarCraft was behaving a lot like an ecosystem. “We have an environment,” says Barbe. “We have resources. We have organisms that are competing in this environment. That’s…

DAMSELS AND DRAGONS Below those bug eyes, hidden behind the leaf, are four pairs of wings that you might mistake for those of dragonflies. Damselflies belong to the same taxonomic order, but are smaller and slimmer than dragonflies. You can tell them apart by how they hold their wings at rest — damsels can fold their four wings along their body, while dragons hold them flat like a moth. There are around 2,600 known damselfly species; in September, researchers from the National Centre for Biological Sciences and the Zoological Survey of India added three more. The new arrivals were found in India’s biodiverse Western Ghats mountain range.…

Anyone can build a tiny habitat amidst the sea of green that is our lawns. Whether it’s a strip of right-of-way outside your urban apartment, your manicured suburban lawn or many mowed acres surrounding your house in the countryside, we’ve all got a little sod we could consider giving back to nature. Researchers have been learning more and more about declines in native pollinators, all while finding out the ways mowed, watered, fertilized and herbicided lawns can negatively affect the environment. That’s why University of Central Florida entomologist Barbara Sharanowski teamed up with ecologist Nash Turley to create the Lawn to Wildflowers program. They’ve developed an app to coach users on how to turn any patch of lawn into native wildflower habitat; it will also collect valuable data. Discover spoke…

Delta-9-THC, the main drug in cannabis plants that gets people high, can also be a potent medicine. It can treat extreme nausea and stimulate appetite, which is especially helpful for people who have HIV or are going through chemotherapy. A synthetic version of THC, called Dronabinol, has been used to treat these conditions since the 1980s. But while marijuana is a relatively mild drug with few side effects — at least, compared to alcohol or tobacco — too much Delta-9-THC has its downsides. It can sometimes spark paranoia and anxiety, or trigger dizziness and headaches. That’s why many cannabis consumers are turning to an obscure analogue of Delta-9-THC called Delta-8-THC. Preliminary evidence suggests the compound might have fewer negative effects, as well as additional medicinal properties. Both THCs are made…

Have you ever held a product in your hands and considered the existential weight of your purchase? Beyond each price tag hides a ripple effect. It expands from soil to waterways, grocery aisles to kitchen plates, factories to fulfillment centers and mail slots to landfills. This global impact has become less hidden in the past decade, and ignoring the people downstream from us has grown increasingly difficult. We’re more aware than ever of the mark our consumption leaves on planet Earth, which now sustains nearly 8 billion people. Somehow, humans are still pumping more than 30 gigatons of carbon dioxide (CO2) per year into the atmosphere, despite the mountain of evidence that CO2 is the top contributor to greenhouse gases causing global warming. Similar conundrums apply to use of plastics…

Place yourself in the heart of the Great Plains, say, somewhere in the Texas Panhandle. A long, lonely stretch of interstate extends before you. Prairie grass and planted wheat cover the landscape out to the horizon, flat as a table in all directions. But it’s not truly flat. Even on these plains there are low spots, the ground sloping almost imperceptibly toward slight, bowl-shaped depressions where the infrequent rains of this semi-arid environment collect. These are playas: wetlands that come and go, providing an oasis for life in an otherwise desiccated place. When wet, playas harbor a plethora of amphibians, waterfowl, dragonflies and other species. But playas don’t just support the lives of birds and toads; they also support humans. Playas replenish the Ogallala Aquifer, a 948-trillion-gallon underground body of water…

Volunteers buzz around the front lawn of a Baptist church in Louisville on a bright October morning. Sporting navy T-shirts with the words Citizen Forester emblazoned across the back, they divvy up spades and shovels, grab buckets and hoses. Behind them looms the church’s imposing white-columned entrance and a sign that declares, “Prayer Works.” Across the street, a row of small clapboard-sided homes stretches down the block. A pair of dogs bark furiously behind a chain-link fence. Then everyone turns to the man in leather loafers and a linen suit coat. His ambitious idea — one that may or may not work — is the reason they’re here. “We all intuitively believe trees are good for you. But we don’t know if it will help the health of the population…