Chinese butchers catch a pig to slaughter on January 31, 2005 in Jinzhai County, Anhui Province, China. (Photo by Cancan Chu/GettyImages)

Soldiers, including two recruits who have brought some chickens, at Victoria prepare to board the train for the battle front. (Photo by Hulton Archive/Getty Images)

The first load of passengers queuing for the Bennie Railplane in Glasgow; the inventor George Bennie is third in the queue. The streamlined cars are self propelled, driven by air screws in front and behind, and hang from a steel girder. (Photo by J. A. Hampton/Topical Press Agency/Getty Images). 4th July 1930

LA Coroners leave the Beverly Hilton Hotel possibly carrying the body of the singer Whitney Houston in the early hours of February 12, 2012 in Los Angeles, CA. Singer and film star Whitney Houston aged 48 has died in her hotel room at the Beverly Hilton Hotel. (Photo/Toby Canham/Getty Images)

Afghan girl athletes perform Wushu on the top of a hill in Kabul, capital of Afghanistan, January 18, 2017. In the conservative Afghan society where people especially in the countryside deeply believe in the old traditions and don't allow their girls and female members of the family to go out of home, exercising sport in open is extremely risky, but a group of girls are broken the taboo and exercising Wushu on a hilltop where the temperature is minus 2 Celsius degrees. (Photo by Rahmat Alizadah/Xinhua/Barcroft Images)

Elementary school children play outside their classrooms as mount Sinabung volcano spews thick volcanic ash in the background on February 10, 2017 in Karo, Indonesia. Mount Sinabung is one of the most active volcanoes in Indonesia and last erupted in May 2016, killing seven people. (Photo by Albert Damanik/Barcroft Images)

Figures of Francois Fillon (L), former French prime minister, member of The Republicans political party and 2017 presidential candidate of the French centre-right, and French National Front leader Marine Le Pen are paraded through the crowd during the 133rd Carnival parade, the first major event since the city was attacked during Bastille Day celebrations last year in Nice, France, February 11, 2017. (Photo by Eric Gaillard/Reuters)

Cheerleaders let their hair fly as they perform prior to a German first division Bundesliga soccer match between 1. FC Cologne and Bayern Munich in Cologne, Germany, March 4, 2017. (Photo by Michael Probst/AP Photo)