A Naga sadhu, or naked Hindu holy man, performs a ritual inside his tent during Kumbh Mela, or Pitcher festival, at Trimbakeshwar, India, Friday, August 28, 2015. Hindus believe taking a dip in the waters of a holy river during the festival will cleanse them of their sins. The festival is held four times every 12 years. (Photo by Rajanish Kakade/AP Photo)

In this September 1, 2015 photo, street artists Jenaro de Rosenzweig, left, and Alejandro Revilla pose for a portrait behind a restaurant's window covered with a mural by artist Francisco Munoz, signed with his artist's name below, in the Roma Norte neighborhood of Mexico City. Rosenzweig and Revilla founded the “Street Art Chilango” cooperative in March 2013, which is filling neighborhoods with public art by local street artists. (Photo by Rebecca Blackwell/AP Photo)

Anand Varma, a U.S. photographer working for the National Geographic, won the First Prize in the Nature Category, Stories, of the 2015 World Press Photo contest with his series of pictures, which includes this one of spores of a fungus landing on an ant, penetrating its exoskeleton and entering its brain, compelling the host to leave its normal habitat on the forest floor and scale a nearby tree, in this picture taken January 22, 2014 and released by the World Press Photo on February 12, 2015. (Photo by Anand Varma/Reuters/National Geographic/World Press Photo)

A statue by Italian artist Maurizio Cattelan of Adolf Hitler praying on his knees in Warsaw, Poland, on Friday Dec. 28, 2012. The work, «HIM» has been drawing visitors since it was installed last month and even some anger. One Jewish group, the Simon Wiesenthal Center, this week condemned the work's placement in the former ghetto as “a senseless provocation which insults the memory of the Nazis' Jewish victims”. (Photo by Czarek Sokolowski/AP via La Presse)

A man dressed as Hindu goddess Kali, the goddess of power, performs with a burning camphor tablet on his tongue during a religious procession ahead of the “Kumbh Mela”, or Pitcher Festival, in the northern Indian city of Allahabad January 6, 2013. During the festival, hundreds of thousands of Hindus take part in a religious gathering at the banks of the river Ganges. The festival is held every 12 years in different Indian cities. (Photo by Jitendra Prakash/Reuters)

A boy poses with a butterfly on his face during a photocall to promote the “Sensational Butterflies” exhibition at the Natural History Museum in central London, on March 25, 2013. With around 400 live tropical butterflies and moths living in the temporary facility, visitors will get the chance to see them flying freely as well as looking for emerging butterflies at the hatchery window. Running from March 29 to September 15, 2013, the exhibition is housed in a structure in the museum grounds. (Photo by Leon Neal/AFP Photo)

Bill Moreau watches as the Black Forest fire burns near his house near Black Forest Road Tuesday afternoon, June 11, 2013, near Colorado Springs, Colo. The Black Forest Fire was one of at least three significant wildfires burning in Colorado amid gusty winds and record-breaking hot, dry weather. (Photo by Christian Murdock/AP Photo/The Colorado Springs Gazette)

A woman crowd-surfs in front of the main stage at the Woodstock Festival in Kostrzyn-upon-Odra, close to the Polish-German border, August 2, 2014. Some 500 thousand people attended the festival that is the brainchild of Polish journalist and social campaigner Jerzy Owsiak. He initiated the event to say thank you to those who donated money to his GOCC charity organisation that delivers medical care for children. (Photo by Thomas Peter/Reuters)