CLOSE

Underground Wonders

More than just a hole in the ground, every cave has its own story. Caves are born in many different fashions, which leave them with different personalities.

Lava Tubes

Lava tube caves are formed when lava flows down the side of a volcano. The lava exposed to the air cools and hardens first, while the lava underneath continues to flow out, leaving an open tube behind when the eruption is finished. The longest and deepest lava tube is 40-mile-long Kazumura Cave on the southeast slope of Mauna Loa in Hawaii.

Tree Molds

435cavetreecast.jpg

Mount St. Helens has plenty of lava tube caves, and some lava tree molds. The tree molds were formed when an eruption 1,950 years ago knocked down trees and covered them with lava. When the trees burned, the opening left behind would be a perfect mold of the logs.

Sea Caves

435caveBlueGrotto.jpg

Sea caves are erosional caves, formed by the action of waves against rock, usually along an existing fault. The Blue Grotto of Capri is a popular and photogenic cave due to the appearance of light from the bottom of the cave. Sunlight enters the cave through underwater channels and reflects off the limestone floor.
More types of caves, after the jump.

Wind Caves

435caveGaviota.jpg

Wind caves are formed by erosion of sandstone by blowing wind. They tend to be pretty shallow and rounded. Gaviota, California is home to some beautifully sculpted wind caves.

Glaciar Caves

435caveFox_glacier.jpg

Glaciar caves are also erosional, usually carved by mountain streams flowing into glaciers, but can also be formed by volcanic heat from below. Pictured is a cave carved by water flowing into the Fox Glacier in New Zealand.

Limestone Caves

435cavemammoth2.jpg

Solutional caves are formed when the existing rock is dissolved. The most common type is the limestone cave, because rainwater and groundwater contain acids which dissolve limestone over time. An example is Mammoth Cave system in Kentucky, the world's most extensive cave system at 367 combined miles (and still not completely mapped)!

435caveSarawak1.jpg
Another limestone cave formation, the Sarawak Chamber in the Gunung Mulu National Park in Malaysia is the world's largest single cave chamber, measuring 2,300 feet long, 1,300 feet wide and at least 230 feet high!

435caveLechuguilla.jpg

In New Mexico, Lechuguilla Cave and Carlsbad Caverns are a different kind of solutional cave. They were formed by sulphurous acids rising from below. The minerals from the acidic fumes leave amazing and fragile gypsum and sulphur formations such as chandeliers, soda straws, and cave pearls. Although Carlsbad Caverns is a major tourist draw, the more recently-mapped Lechuguilla Cave is off-limits to visitors in order to preserve the environment.

Salt Caves

435caveNamaktunelIran1.jpg
Salt caves are also solutional caves, forming and collapsing relatively quickly. The world's longest salt cave (nearly four miles) was discovered just last year on Qeshm Island off the coast of Iran.

For all kinds of information on caves, I recommend a tour of The Virtual Cave.

nextArticle.image_alt|e
iStock
arrow
Live Smarter
Which Rooms In Your Home Have the Most Types of Bugs, According to Entomologists 
iStock
iStock

Insects can make any home their own, so long as it contains cracks, doors, and windows for them to fly, wriggle, or hitchhike their way in. And it turns out that the creepy crawlers prefer your living room over your kitchen, according to a new study that was recently highlighted by The Verge.

Published in the journal Scientific Reports, the study looked at 50 homes in Raleigh, North Carolina, to measure their insect populations. Entomologists from both North Carolina State University and the California Academy of Sciences ultimately discovered more than 10,000 bugs, both alive and dead, and a diverse array of species to boot.

The most commonly observed bugs were harmless, and included ladybugs, silverfish, fruit flies, and book lice. (Luckily for homeowners, pests like bedbugs, termites, and fleas were scarcer.) Not all rooms, though, contained the same distribution of many-legged residents.

Ground-floor living rooms with carpets and windows tended to have the most diverse bug populations, as the critters had easy access inside, lots of space to live in, and a fibrous floor habitat that could be either a cozy homestead or a death trap for bugs, depending on whether they got stuck in it. The higher the floor level, the less diverse the bug population was, a fact that could be attributed to the lack of doors and outside openings.

Types of bugs that were thought to be specific to some types of rooms were actually common across the board. Ants and cockroaches didn’t limit themselves to the kitchen, while cellar spiders were present in all types of rooms. As for moths and drain flies, they were found in both common rooms and bathrooms.

Researchers also found that “resident behavior such as house tidiness, pesticide usage, and pet ownership showed no significant influence on arthropod community composition.”

The study isn’t representative of all households, since entomologists studied only 50 homes within the same geographical area. But one main takeaway could be that cohabiting bugs “are an inevitable part of life on Earth and more reflective of the conditions outside homes than the decisions made inside,” the researchers concluded. In short, it might finally be time to make peace with your itty-bitty housemates.

[h/t The Verge]

nextArticle.image_alt|e
iStock
arrow
technology
Special Viewfinders Allow Colorblind People to Experience Fall Foliage in All Its Glory
iStock
iStock

Each autumn, the foliage of the Great Smoky Mountains erupts into a kaleidoscope of golds, reds, and yellows. Visitors from around the world flock to the area to check out the seasonal show, and this year some guests will have the chance to see the display like they’ve never seen it before. As the Associated Press reports, Tennessee is now home to three special viewfinders at scenic overlooks that allow colorblind users to see the leaves of the forests in all their glory.

The new amenities cost $2000 apiece and have been installed by the Tennessee Department of Tourist Development at the Ober Gatlinburg resort, at Big South Fork National River and Recreation Area near Oneida, and at the westbound Interstate 26 overlook near Erwin in Unicoi County. The lenses are similar to glasses that allow people with red-green vision disorders to see in full color, but according to state officials this is likely the first time the technology has been implemented in scenic tower viewers.

Color blindness varies from person to person, but those who have it may tend to see mostly green or dull brown when looking at a brilliant autumnal landscape. Before the new features debuted at the beginning of November, tourism officials allowed a group of colorblind individuals to test them out. You can watch their reactions to seeing the true spectrum of fall colors for the first time in the video below.

[h/t AP]

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios