EarthDate

Besides a few very committed scientists, there’s only one organism that can live on the continent of Antarctica year-round. It’s not a penguin or a seal; they live mostly at sea. No, it’s the tiny Antarctic midge, just a quarter inch long and extremely adapted to the extreme environment. Midges are small insects that usually fly and bite hosts to feed on blood. The Antarctic midge does neither. Li...

On November 1, across Latin America but especially in Mexico, the cemeteries come alive—with a celebration. It’s Dia de los Muertos, the Day of the Dead. Legend has it the gates of heaven open for a day to allow the souls of the dead to reunite with loved ones. It’s considered disrespectful to mourn the dead, so families bring food and drink, clean and decorate gravestones, sing, and dance, fly br...

Here are two trivia questions for you: What’s the strongest metal on Earth? And why is it called “wolf cream”? It was discovered in the 1400’s when miners found a hairy black mineral with tin ore. When they smelted the two together, the surface of the melted ore foamed and a heavy slag consumed much of the tin. They named the mineral “wolf” for its furry appearance and appetite for tin and “rahm”...

Mesopotamia, in the Middle East, is known as the birthplace of civilization. Two of its early civilizations mysteriously collapsed, which baffled researchers until they found the reason—in stalagmites. Around 10,000 years ago, hunter-gatherers there developed agriculture and domesticated animals. Abundant food and animal labor allowed them time to invent: the wheel, glassmaking, and eventually wri...

As we know, birds descended from dinosaurs. And with 18,000 species of bird now living, there may be more “dinosaur” species today than ever before. The birds that share the most DNA with their dinosaur ancestors are, surprisingly, the chicken and the turkey. The turkey, like the tyrannosaur, has a wishbone and a similar hip structure. And it has meaty drumsticks and thighs like a Velociraptor. Yu...

We’ve talked before about how lightning breaks nitrogen molecules into nitric oxide—which falls to Earth in rainwater and nourishes plants. But we now know that lightning storms have another essential function. After forming nitric oxide, a secondary reaction makes oxidants, which clean the atmosphere. Oxidants are essentially water molecules that lost a hydrogen atom. To replace it, they react wi...

Whakaari/White Island is New Zealand’s largest active volcano. Its crater forms a huge natural amphitheater that opens to a bay. In December 2019, a large group of tourists arrived for a day trip. They donned gas masks to watch fumaroles spew clouds of yellow steam. Then, disaster struck. The volcano erupted suddenly, belching vapor and ash two miles into the sky. The cloud collapsed into the amph...

We’ve talked a lot about fossils on EarthDate, but we’ve never talked about how they form. Normally, when a plant or animal dies, it decays or is consumed. But occasionally its remains are preserved as a fossil. This usually happens when the organism is buried quickly in sediment. The sediment layer protects it from the elements, scavengers, even oxygen. Often soft parts decompose, leaving bones,...

Until Marie Tharp came along, no one knew what the seafloor really looked like. It was long thought to be a featureless plain of mud. Then sonar, invented in World War II, began to give us a glimpse. But it could only “read” the bottom of the ocean right below the ship’s path. Marie Tharp earned master’s degrees in geology and mathematics in the 1940’s and joined the navy to study the seafloor—but...

Bloodletting with leeches seems a very primitive practice. So, it may surprise you to know it’s still very much in use today. There are 700 species of leech. Most dwell in water and drink blood from fish, turtles, ducks, frogs and other creatures. Scientists can even track which animals are living in swamps and rainforests by capturing leeches and DNA testing the blood in their stomachs. Leeches w...

DNA is like a fingerprint. Each species’ DNA signature is distinctive. And it can be found on the scene long after the individual has gone. For some time, scientists have gathered the DNA that organisms leave behind—in saliva, urine, feces, fur, and flakes of dry skin—to detect their presence and study them. They’ve found this so-called environmental DNA, or eDNA, in water, soil, even snow. But sc...

When the explorer Ferdinand Magellan finally made it ‘round the treacherous horn of South America in 1521, the ocean beyond seemed especially calm—so he named it the peaceful sea: Mare pacificum, the Pacific Ocean. Little did he know the Pacific is anything but. It’s surrounded by more than 1,000 volcanoes that make up what’s now called the Pacific Ring of Fire—a geologically active strip 25,000 m...

Think about this: a tree could be 100, 200, more than 300 feet tall, yet can lift water from deep underground all the way to the leaves of its highest branches. Each day it could move hundreds of gallons, several tons of water this way. This gravity-defying feat is made possible not so much by the tree but by the properties of water itself. Trees perform photosynthesis in their leaves, which requi...

There’s a common houseplant that in the wild can do what no other plant can. It’s the staghorn fern. It’s an epiphyte, meaning it doesn’t need soil but instead grows on a larger host plant and draws its nutrients from water and air. But that’s not what makes it unique. Normally a staghorn has two types of fronds. One is green, antler shaped and produces spores. The other is brown, strap-like and s...

You’ve probably heard that black cars get hotter than white cars. Scientists set out to measure the difference. They parked two otherwise identical cars in a sunny parking lot, and, sure enough, the white car’s interior stayed 17 degrees Fahrenheit cooler. Urban planners hope to use the same principle to cool cites, where miles of black asphalt and dark colored roofs absorb the sun’s heat, amplify...

There’s a special place in South Africa called Border Cave where our ancestors already in modern human form lived continuously for nearly a quarter million years. Excavating in the cave is like reading backward in a history book, finding evidence of each earlier generation in each deeper layer. The cave has yielded 69,000 artifacts, a treasure trove of clues to human prehistory, and digs continue...

There’s one source that provides almost a third of the water for all US agriculture. It’s called the Ogallala aquifer, stretching under the Great Plains from South Dakota to northern Texas. Once considered inexhaustible, we now understand its limits. For the first settlers in the Great Plains, water was scarce and farming was difficult… Until the 1850s, when they began to use windmills to pump up...

Tiny mosses were the first land plants to evolve on Earth. But the first real plants, the big leafy kind, came on the scene 400 million years ago—200 million years before hardwood trees and flowering plants. I’m talking about ferns. They flourished, then and now, through a unique two-stage life cycle. Mature ferns produce spores that drop to the ground. There they grow into gametophytes, which don...

It may surprise you to know that one of the most important minerals in history has been … potash. Many centuries ago, humans discovered that if you took a pot, put in wood ash, boiled it then strained out the residue, you’d get potash—which had two very special qualities. First, when mixed into soil it made an excellent fertilizer for crops. Second, when mixed with sulfur and charcoal it made gunp...

Some very old oyster shells found in a cave have answered the eternal question, “who was the first person to eat that”?! Looks like it was a hungry South African, 164,000 years ago. Today, we consume around 8 billion oysters a year. But they’re good for so much more than eating. Oysters cement themselves together to form reefs that control coastal erosion and reduce wave energy. These reefs increa...

Only one ten thousandth of Earth’s total water supply is fresh water on the surface, to keep billions of humans and other animals alive. Good reason to conserve it—which also saves energy and money. Water is heavy, so it takes energy to move it. The farther it’s pumped in pipelines or carried in trucks, the more it costs the user. Water purification systems also require energy, adding to the price...

The word monsoon may conjure in your mind torrential rains. But monsoon actually comes from the Arabic mawsim—meaning not rain but season. In the tropics, there are only two seasons, known as dry and wet monsoons. They’re brought about by equatorial winds that blow in each spring and fall—predictably enough that sailors have depended on them for centuries. During wet monsoons, the winds bring rain...

The meteorologists who invented weather radar never expected to be studying bugs. But today they do. There are 159 weather radar stations in the US. They look like giant golf balls on towers. There’s a rotating dish within the white sphere that sends radio pulses into the sky. When they meet something, some of the radio waves bounce back. The radar reads the time and strength of the returned waves...

A recent discovery has reshaped our understanding of human history in North America. A few EarthDates ago, we talked about a tribe of Siberians who were stranded in the Bering Strait for centuries before migrating into North America to become its first citizens 16,000 years ago. Turns out, they weren’t first. Because in White Sands National Park, scientists have found something remarkable. Modern...

At the bottom of one of Africa’s deepest lakes lies a secret that could put two million nearby residents in danger. Lake Kivu sits along the East African Rift Valley, where the tectonic plates that bisect Africa pull apart. Volcanoes leak natural carbon dioxide into the bottom of the lake, where the water pressure is high enough to dissolve and concentrate the gas in water. If the water temperatur...