A competitor scrambles in the mud under barbed wire during the Tough Guy Challenge 2009 at South Perton Farm on February 1, 2009 in Wolverhampton, England. The biannual event to raise cash for charity challenges thousands of international competitors to run through a gruelling set of 21 obstacles including water, fire and tunnels after a lengthy run at the start. (Photo by Christopher Furlong/Getty Images)

An authenticated contemporary copy of Leonardo da Vinci's Mona Lisa on display at the Prado Museum on February 1, 2012 in Madrid, Spain. Experts of the Prado Museum say the copy was painted at the same time as the Mona Lisa in Leonardo Da Vinci's studio by one of his students.

Kat Von D attends her first solo art show “New American Beauty” at Sephora Antara store on March 1, 2012 in Mexico City, Mexico. (Photo by Victor Chavez/Getty Images For Sephora)

California-based photographer Seth Casteel made his name taking photographs of dogs underwater, but before that, he was snapping cats on land.

Irene Aguirre, 23, attends a boxing class at the National Institute of Sport in Managua March 4, 2015. A study done by the Psychology alumni of the National Autonomous University of Nicaragua (UNAN-Managua) revealed that about 1 million women in Nicaragua suffer from domestic violence. (Photo by Oswaldo Rivas/Reuters)

Couples participate in the “Running of the Brides” race in a park in Bangkok November 29, 2014. Seventy-five husbands and wives-to-be wore their wedding dresses and running shoes and competed in an event for a combined prize worth 1 million Thai baht ($30,460). (Photo by Damir Sagolj/Reuters)

Sushi chef Mitsuru Tamura uses a radiation detector on seafood before it is prepared in Manhattan's Sushi Yasuda restaurant April 8, 2011 in New York City. The restaurant has begun using the detector as a precautionary measure due to consumer concerns over possible radiation contamination in seafood from the nuclear emergency in Japan. Health officials believe contamination is unlikely to threaten the food supply chain and none has been found in this restaurant. (Photo by Mario Tama/Getty Images)

Conjoined twins Angelica (C) and Angelina Sabuco (L) play with child life specialist Allison Brooks during a press conference at the Lucile Packard Children's Hospital at Stanford on October 31, 2011 in Palo Alto, California. Two year-old conjoined twins Angelica and Angelina Subaco who are connected at the chest and abdomen are preparing for separation surgery by Dr. Gary Hartman. The surgery will last between 6 and 8 hours that is followed by three hours of reconstructive surgery for each girl. (Photo by Justin Sullivan/Getty Images)