Earth Science

Subsidence, or the decline in the elevation of land surface, is creating a problem for some coastal cities as sea levels rise.

By Jesslyn Shields

Here are six surprises that were uncovered around the globe when the heat rose and the water receded.

By Cherise Threewitt

Birds are — quite literally — living dinosaurs. Our quiz will test your knowledge of the fluffy, downy and winged dinos of the bygone Mesozoic era, from little Microraptor to the enormous Yutyrannus.

By Mark Mancini

Each year, Earth sees two equinoxes and two solstices. But how much do you actually know about these events? Take the quiz and find out!

By Alia Hoyt

Water surrounds us, falling from the sky and pouring from faucets, and yet many of us never ask where it comes from. The answer stretches way back — before tides and thunderclouds to the big bang.

By Jonathan Atteberry & Ian O'Neill, Ph.D.

To honor their prehistoric pasts, most U.S. states have designated official state fossils, ranging from trilobites to dinosaurs. Take our quiz to learn more!

By Mark Mancini

All that seashell collecting you've been doing actually hurts the environment.

By Mark Mancini

Decades after the massive conflict, reminders of battles linger in pristine Pacific waters.

By Christopher Hassiotis

The ocean’s depths are one of the most mysterious areas on the planet – and the inhabitants of this murky domain are stranger than anything you’ll find on land.

Decades of fossil discoveries have revealed much about the extinct members of our hominid family tree, but we're far from having all the answers. What have we learned from some of these fascinating finds?

By Jane McGrath

Do you ever play that game in which you select the items you'd bring if you got stuck on a desert island? Along with that treasured bootleg recording of your favorite band, we think that an endless supply of water should be at the top of your list. Here's why.

By Jonathan Atteberry

The world of our far-future descendants may be as unrecognizable to us as our bustling, urbanized world would be to our bewildered ancient forefathers. Will energy drive many of those changes?

By Robert Lamb

A common misconception is that magma comes from the Earth's molten core. It really comes from the mantle, the layer between the core and the crust. Will it ever run out?

By Tracy V. Wilson

The Doll's Theater of Carlsbad Caverns looks otherworldly and took ages to form. What other incredible sights await us below ground?

By Julia Layton

Huge walls of cascading water never cease to capture our attention with their majesty. Ready to marvel at nature? Check out some of the most beautiful waterfalls in the world.

By Rick Mayda

Early explorers drove flags into the ground to claim territories. But no one bothered to float a flag in the oceans. For the most part, we peaceably shared the oceans until we realized what valuable goods could be found in their dark and murky depths.

By Josh Clark

Ocean currents can have an incredible impact on Earth's weather. This gallery of images shows how powerful ocean currents can be in the environment.

By Rick Mayda

Whether you sail, surf, fish or collect shells, having one of these could help you out before you hit the water.

By Jennifer Horton

Diamonds are some of the most brilliant and expensive natural features Earth has to offer. This collection of images displays diamonds in all their uncut and polished shapes and sizes. Obligatory pictures of very large diamonds are included of course.

By HowStuffWorks.com Contributors

One grows from the ground and one from the ceiling, but sometime's it's hard to remember which is the stalactite and which is the stalagmite. How do they get there, anyway?

By John Fuller

Few Americans like the switching between Daylight Saving Time and Standard Time, but there's conflict on whether to switch permanently to DST or to ST. What are the pros and cons of permanent DST?

By Allison Troutner

Nutty Putty Cave, near Salt Lake City, Utah, was discovered in 1960 and sealed up forever in 2009. But why?

By Dave Roos & Austin Henderson

Cinnabar's bright-red pigment has been used in jewelry, pottery and makeup for millennia. But cinnabar is also the primary ore for mercury, making it a dangerous mineral if the particles are inhaled.

By Allison Troutner

There are caves all over the world, but some are in places that are hard to explore — hidden by rocks, ruins or even under ice. We've found seven secret caves you probably never knew existed.

By Stephanie Parker

The waters of the Atlantic and Pacific oceans meet at the tip of Cape Horn and never the two shall mix, right?

By Jesslyn Shields