Episodes

Wondering what to get that special someone for Halloween? How about a bouquet of corpse flowers? Of course, you’ll have to go all the way to Indonesia to get them. And it would be a very, very large arrangement. There are two types of corpse flowers, and both emit a strong odor of rotting meat to attract flies and beetles to pollinate them. Titan arum lives up to its name, with flowers topping 10 feet in height. To produce a bloom of such staggering proportions, it spends a few years as a small ...

Phoenician soldiers, when injured in battle, would shave bronze from their swords into their wounds. Why? For the copper. Copper is often found in its pure state, rather than bound in ore, and is easy to bend. This made copper the first metal to be shaped by humans into useful implements around 10,000 years ago. The Copper Age lasted 5,000 years, until someone realized they could add tin to copper to make bronze, which was easier to melt and cast, harder as a finished product, and better for too...

Have you ever seen a gecko walk straight up a glass door, or sprint upside down across a ceiling, and wonder, “How can they do that?” To get the answer, you’d need an electron microscope. At 200× magnification, you’d see the gecko’s toes are covered with tiny hairs called setae. Zoom in closer and at 1000×, you’d see that the setae are actually bunches of hairs, like in a hairbrush. Much closer, at 55,000×, you’d see that each one of those hairs splits again into hundreds of branches of spatulae...

California gray whales, like several other whale species, migrate from arctic feeding grounds in summer to warm equatorial waters in winter to birth their young. This migration can be more than 13,000 miles—the longest on Earth. Scientists think they may use magnetoreception, navigating according to Earth’s magnetic field. New findings somewhat corroborate that, but with a wrinkle we can’t explain. It’s not uncommon that whales will get lost or injured along the route, strand themselves on the c...

Around September 23rd and March 20th each year, visitors gather at ancient monuments to witness the equinox. On these two days, day and night are equal everywhere on the planet. The sun rises exactly in the east and sets exactly in the west. Ancient architects, astronomers, and priests collaborated to align many structures with the equinox sun to create spectacular light effects. In a 5,000-year-old underground Celtic temple, the rising sun penetrates a long shaft to light an engraved wall. At a...

When passengers boarded a British Airways flight from New York to London on February 8, 2020, they had no idea they were about to make history. Once their 747 reached cruising altitude, the pilots directed the plane into a jet streak, a fast-moving current of air that sometimes occurs in winter. The streak rocketed the plane to a ground speed of 825 miles an hour, cutting travel time by 25 percent and setting a record for subsonic aircraft making the trip. The surprised passengers arrived in Lon...

On another EarthDate you heard that bees are dying. While it’s common for a hive to lose 15% of its bees each winter, rates since 2007 have sometimes hit 40%. This has scientists concerned, and after a decade of research, they’ve traced the bees’ troubles to several factors. First, stress. A decrease in wild acreage means fewer wild bees, so that more commercial bees are needed for pollination. This has the hives traveling farther and more frequently. Rising temperatures also have an impact, mak...

Nickel is in demand because it’s used in lithium ion batteries, common alloys such as stainless steel, and new super alloys for the aerospace and wind turbine industry. But mining and smelting nickel is energy intensive, using a great deal of diesel fuel and coal. And the after-products are environmentally dangerous. Luckily, we’ve found that nickel can grow on trees. Or more specifically, shrubs. Metals are toxic to most plants, which don’t grow in metal-rich soils. But some 700 species are hyp...

Even if you’ve watched documentaries about honeybees, you may know little of their remarkable life within the hive. A queen will lay a million eggs in her 5-year lifetime, which she places in wax brood cells. Fertilized eggs grow into sterile female workers. Unfertilized eggs become male drones. When the queen gets old, nurse bees bathe regular female larvae in royal jelly, which turns them into queen larvae. The queen that emerges first will kill the other larvae to become sole heir to the thro...

Honey is a miraculous substance, containing enzymes, vitamins, minerals, and antioxidants. But it’s not the only amazing thing bees make in the hive. Honey starts as nectar that bees gather from thousands of flowers on foraging flights. The bees store the nectar in a special sac next to the stomach. On returning to the hive, they transfer it to the mouths of waiting worker bees. Workers ingest and regurgitate the nectar over and over for several minutes. Their digestive enzymes convert the sucro...

Bees make over $300 million worth of honey, beeswax, propolis, and other products each year in the U.S., which we eat and use in medicines, cosmetics, even varnishes. But the real big business of bees is the billions of dollars keepers earn pollinating crops. Bee colonies are treated, and valued, like livestock. The keepers move the hives to the best positions for most effective pollination on a strict schedule, following the flowering of crops across the country. They start in February, in Cali...

It seems that Australia’s modern highways may have been laid out according to the stars. Australian Aboriginals, like many ancient cultures, have an elaborate oral history passed down through generations to help them navigate and find food and water in their desert environment. This knowledge base uses visual memory aids from the land… and the sky. When ancient aboriginal navigators found a successful path through the desert, they looked for a path in the stars that mimicked it. They’d use stars...

You’re about to hear what may be the oldest story ever told. In another EarthDate, we talked about how Australian Aboriginals remember star maps using songs. But their oral history has preserved much more in stories that corroborate ancient geological events. For instance, they tell of a dramatic sea-level rise long ago that inundated areas of the coast. Many tribes, separated by great distance and different languages, tell the same story. And the details match the geological record of 7,000 yea...

In many parts of the U.S., what we call “locusts” are actually cicadas—that plug-shaped insect that sings in the trees. But especially in Africa and the Middle East, “locusts” are large grasshoppers occurring in massive swarms that can devour crops across the region. These grasshoppers have undergone a strange metamorphosis. In normal times, they’re a shy, solitary desert hopper. Heat and drought control their numbers, and they’re not a threat to agriculture. But every few decades—when heavy rai...

Do you wish you could have an extra hour in the day? Well, if you can wait a very long time, you’ll get it. That’s because the length of the day is increasing, and has been for the last billion-plus years. Scientists recently studied a large Cretaceous mollusk with unprecedented precision. Mollusk shells grow like tree rings, adding a little bit each day. The researchers used lasers to drill tiny holes in the shell, each the size of a red blood cell—like microscopic core samples. From these they...

75 years ago, the U.S. exploded its first atomic bomb, in the New Mexico desert. It was the culmination of 5 years of hurried development. Throughout World War II, Germany hoped to use the incredible energy density of uranium and plutonium to build a devastating weapon. To beat them to the bomb, the U.S. assembled teams across the country—130,000 staff and scientists, many of whom had fled Europe to avoid Nazi persecution. In July 1945, team leaders gathered to watch that first detonation from 1...

Today, emeralds may be a bit less famous than their red, white, and blue cousins—diamonds, rubies, and sapphires. But they were once perhaps the most celebrated gemstone. 3,500 years ago, the Egyptians found emerald deposits in their kingdom. They ascribed to the stones many mystical properties. They were symbols of fertility and immortality, perhaps because of their “ever green” color. They were thought to increase eloquence and intuition. Some even thought they could cure malaria. Those who pu...

Machu Picchu, the Incan city built on a jagged mountain peak, is so remote that the Spanish conquistadors never found it. It’s difficult to get to, even today. We’ve long wondered why the Inca built it there. New research suggests they chose the site because it’s on the intersection of fault lines. That would seem like a terrible place to build any city! But the Inca had good reasons. The faults would have fractured the rocks there, making it easier for the Inca to dig and build flat terraces on...

If you’ve ever walked through an aspen grove, you’ve seen hundreds or thousands of white trunks propping up a sky of silvery green leaves trembling in the wind. In the fall, all the leaves in one grove will go from green to gold at the same time. This is because the entire grove is really just one organism, a massive root system from which many trunks sprout, grow, die, and are replaced by new trunks. The largest aspen grove in the world, in Utah, is named Pando: Latin for “I spread out.” It spr...

When you see white, you’re actually seeing all the visible colors of light at once. And when you see black, the object you’re looking at is absorbing light. White and black aren’t colors; they’re visual experiences. And a few rare animals can produce the visual experience of super-black. Most black surfaces are still slightly reflective. But these creatures have developed plumage or cells that absorb nearly all visible light. The male birds of paradise in Papua New Guinea have super-black feathe...

On a previous EarthDate we talked about GPS, the Global Positioning System, and recent improvements that allow mapping down to the millimeter—accurate enough to detect the creeping movement of Earth’s tectonic plates. These advances have inspired scientists to use GPS in many new ways to better understand earthquakes and other Earth processes. The signals from GPS are very long—many thousands of digits—making them too slow to track seismic activity. But recently, scientists realized they could u...

North America’s Great Lakes are great indeed. They contain 20 percent of the planet’s surface freshwater—enough to cover the continental U.S. 10 feet deep. They formed at the end of the last Ice Age, when Canada was under an ice sheet 3,000 to 9,000 feet thick. This massively heavy continental glacier had flowed southward, depressing and carving the Earth as it passed over, pushing ahead of it huge piles of eroded rock and gravel called glacial moraines. 20,000 years ago, the ice sheet finally b...

In previous episodes, we’ve talked about geothermal energy—the heat of the earth. Where extreme heat is near the surface, it can be used to produce steam to drive electric generators. Where this heat warms groundwater, it makes hot springs. But there’s another type of geothermal energy that’s more widely available: not extreme heat, but constant, low-temperature heat. Anywhere in temperate latitudes, if you dig 10 feet or more below the surface, the ground is a near-constant mild temperature all...

In two earlier episodes, we talked about the greatest environmental disaster in U.S. history: the Dust Bowl, which killed thousands and left millions homeless. It happened when the Great Depression and prolonged drought coincided, causing farmers to abandon their fields across the Great Plains. Winds carried a billion tons of soil into the air, creating devastating dust storms that blew across the country. The Dust Bowl era began in 1931. What ended it? As early as 1933, the government establish...