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Into the Dark Unknown

Some days Louise Hose puts on a suit to go to work. Other days she braids her long blond hair and puts on a helmet with a large head lamp. Sometimes she even wears a gas mask and kneepads. When she isn't dressed up to teach geology courses at Westminister College in Missouri, Hose explores and maps caves--the deeper and darker, the better.

Hose is a geologist and a speleologist, or caver. Her job is to add to our knowledge about how the earth is formed. Sometimes she crawls on her back through tight passages with rock pressing into her body. Other times she rappels, or dangles on the end of a secured rope, down the wall of a deep cave.

For the past few years, she has gone to Tapijulapa (Tah-pee-hoo-la-pa), Mexico, during school breaks to map a cave. She and her fellow explorers found that it is full of animals that have adapted to life underground. There are vampire bats, spiders and colorless fish and crabs that swim in the cave's streams.

They also discovered something more amazing: colonies of microscopic living creatures that can survive in poisonous air and with no light. Such creatures may give clues to what life forms are like in space. These living colonies drip down like a runny nose. They contain sulfuric acid, which can burn human skin. A photographer on the expedition named the slimy critters "snottites."

"Caves are one of the last parts of the earth that aren't mapped yet," says Hose. "It's true exploring." She likes charting the unknown. "When you start 'pushing' a cave--being the first one to go through--you don't know what you are going to find," she says. Sometimes she finds minerals--sparkling gypsum, calcite and aragonite--that shimmer in her head lamp.

When Hose was a kid in Alhambra, California, she loved to watch adventure documentaries. But the brave explorers she saw were always men. "I used to wish I was a boy, so I could be an explorer," she recalls. "Thank goodness I studied geology." Her college studies gave her confidence to discover new worlds: "Girls can and do become explorers."

Next: Top 5 Deadliest Snakes