Sculptures entitled “The Rising Tide” by British sculptor Jason deCaires Taylor are seen beside the River Thames in front of the Houses of Parliament and the London Eye ferris wheel in London, September 3, 2015. The representations of four horses and riders are fully visible at low tide but become immersed underwater twice a day as the Thames rises to reach full tide. The installation will be on display throughout September as part of the annual Totally Thames festival. (Photo by Toby Melville/Reuters)

Residents carry a slaughtered pig with a bamboo pole as they walk home on a street, which was shut to traffic due to ice, in Leishan county, Guizhou province January 31, 2015. Blizzards and icy rain that lasted for several days at the end of January have disrupted traffic, collapsed houses and decimated crops in central Chinese provinces, Xinhua News Agency reported. (Photo by Reuters/Stringer)

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 Palestinian youth practices his Parkour skills over the ruins of houses, which witnesses said were destroyed during a seven-week Israeli offensive, in the Shejaia neighborhood east of Gaza City October 1, 2014. Some Palestinian youths aged between 13 and 17 years old, train in the devastated area as a personal initiative to develop their skills. Parkour is a physical discipline of movement focused on overcoming obstacles. (Photo by Mohammed Salem/Reuters)

Vitor Martins puts forward his fist, that has the word “God” tattooed on it, in front of his Santa Claus outfit inside his house, before a performance with children in Sao Caetano do Sul's town square, near Sao Paulo, December 7, 2014. Martins has dressed as Santa Claus, working at shopping centres and various events, for fifteen years, and has 94 percent of his body covered in tattoos, with several in reference to Christmas. (Photo by Nacho Doce/Reuters)

A German Air Force Officer sits astride a dead boar outside a house where he is stationed near the Western Front, in this 1918 handout picture. This picture is part of a previously unpublished set of World War One (WWI) images from a private collection. The pictures offer an unusual view of varied and contrasting aspects of the conflict, from high tech artillery to mobile pigeon lofts, and from officers partying in their headquarters to the grim reality of life and death in the trenches. The year 2014 marks the centenary of the start of the war. (Photo by Reuters/Archive of Modern Conflict London)

Demonstrators take part in a mass “face-sitting protest” outside the Houses of Parliament in central London on December 12, 2014, as they protest against changes to p*rnography regulations. An amendment to the 2003 Communities Act applies the same strict rules to p*rn bought online as those included in the guidelines set out by the British Board of Film Censors for DVDs. The new laws ban films that feature s*x acts, such as spanking, caning, strangulation, aggressive whipping, humiliation, and face-sitting. Ministers say the rules have been brought in to protect s*x workers. But campaigners say it is an attempt to censor and control the internet. Paid-for videos shot overseas and viewed online in the UK are not affected by the new rules, which were introduced on December 2, 2014. (Photo by Leon Neal/AFP Photo)