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Scientists have routinely gone to the limits of human experience in the name of discovery. But whereas doctors in the olden days would steal cadavers from the morgue or test experimental medicines on themselves and their families, most scientists have left such extreme measures behind — for the most part, that is.
From cave diving to wild lab work, here are seven of the most extreme jobs that keep scientists on their toes today.
Cave diverSlide 2 of 15
Scuba divers probing hidden, underwater caves face terrifying odds. A few wrong kicks can release huge amounts of sediment, creating a complete blackout that leaves them hopelessly lost in the depths with a rapidly depleting oxygen supply. Between 1969 and 2007, 368 Americans died while cave diving, according to a 2009 study detailed in the International Journal of Aquatic Research and Education.
But these treacherous caves can also reveal new insights into ancient Earth's climate and the ecology of islands. In 2010, a team of divers in the Bahamas, including anthropologist Kenny Broad of the University of Miami, ventured into blue holes — giant sinkholes filled with water that form underwater caves — to uncover the climatic history of the region. In a NOVA documentary, the team found that ancient alligators and turtles had once lived in the area but disappeared right around the time when humans first arrived on the islands. [Look Out Below! 8 Amazing Sinkholes]
Just a few months after the film aired, the photographer for the project, explorer and filmmaker Wesley Skiles, died while diving on a reef off the coast of Florida.Slide 3 of 15
Saturation diverSlide 4 of 15
Not all scientific endeavors are deadly — some are just otherworldly and uncomfortable.
Most scuba dives can last only a few hours.
"You can only spend so long at a certain depth, because your body absorbs nitrogen, which is an inert gas," said M. Dale Stokes, an oceanographer at the University of California, San Diego, Scripps Institution of Oceanography in La Jolla, Calif.
If divers stay underwater too long or come up too quickly, the dissolved nitrogen forms bubbles that expand, causing a person's blood to froth like a bottle of shaken-up seltzer — a phenomenon known as "the bends."
To avoid getting the bends, scientists can actually live at the seafloor, in an underwater lab called Aquarius off the coast of Florida. The Aquarius trailer is pumped with air from above the ocean and kept as dry as possible. [Entering Aquarius – Undersea Lab Video Tour]
"You're living down there in a bubble of air on the seafloor," Stokes said.
Divers can live there for up to two weeks. They venture from the trailer with scuba suits and oxygen tanks to spend hours exploring the nearby reefs.
While the setup helps scientists avoid the bends, it's not exactly "home sweet home."
"It's not romantic. You easily pick up skin infections and ear infections. Your body is damp and never really dries out," Stokes said.Slide 5 of 15
Venom milkerSlide 6 of 15
Scientists who study venom often go to extreme lengths to get it. Venom milkers handle the deadliest snakes, such as the krait, along with venomous lizards and sharks. Milking a venomous snake is no easy business. Not only does the person have to find many, many snakes in order to get a decent amount of venom, but the milker then has to take the snakes out of their enclosures and press their fangs to a plastic plate or tube while gently massaging the venom glands. Most of these intrepid scientists have been bitten, sometimes more than two dozen times.Slide 7 of 15
AstronautSlide 8 of 15