Without the use of any type of scuba equipment, divers descend to great depths armed with underwater guns, harpoons and strong line to stalk and hunt prey. Some of the best free-divers in the world can hold their breath for up to 5 minutes under water and go to depths greater than 100 feet.

(All photography © Eyeconic Images.)

In this June 29, 2015 photo, forlorn buildings are seen at Hashima Island, commonly known as Gunkanjima, which means “Battleship Island”, off Nagasaki, Nagasaki Prefecture, southern Japan. The island is one of 23 old industrial facilities seeking UNESCO's recognition as world heritage “Sites of Japan's Meiji Industrial Revolution” meant to illustrate Japan's rapid transformation from a feudal farming society into an industrial power at the end of the 19th century. UNESCO's World Heritage Committee is expected to approve the proposal during a meeting being held in Bonn, Germany, through July 9. (Photo by Eugene Hoshiko/AP Photo)

NASA says it could be another 20 years before humans touch down on Mars, but in a sense, the Mars Society has been exploring the red planet for more than a decade – in Utah. Photo: Csilla Orgel, a geologist of Crew 125 EuroMoonMars B mission, makes her way back to the Mars Desert Research Station (MDRS) in the Utah desert March 3, 2013. The MDRS aims to investigate the feasibility of a human exploration of Mars and uses the Utah desert's Mars-like terrain to simulate working conditions on the red planet. Scientists, students and enthusiasts work together developing field tactics and studying the terrain. All outdoor exploration is done wearing simulated spacesuits and carrying air supply packs and crews live together in a small communication base with limited amounts of electricity, food, oxygen and water. Everything needed to survive must be produced, fixed and replaced on site. (Photo by Jim Urquhart/Reuters)

Chinese woman Zhang Jing, known as the “Ugly Girl” smiles after doctors removed the stitches from her fourth session of cosmetic surgery at a hospital on March 23, 2005 in Shanghai, China. Zhang Jing, 26 years old, from Tianjin Municipality, was forced to leave school because her classmates sneered at her appearance during her teenage years. After leaving junior high school, Zhang found herself still unacceptable by society, she struggled to look for a job, but was turned down by one thousand job applications in ten years. Zhang's story was widely reported by the media in 2003, this helped her find a job and get three chances of free plastic surgery. (Photo by China Photos/Getty Images)