Iraqi security forces take part in training, as they prepare to fight against militants of the Islamic State, at a training camp on the outskirts of Mosul January 10, 2015. (Photo by Azad Lashkari/Reuters)

One of the poor families collecting firewood from the street and the burn to feel some warmth in Aleppo, Syria on August 19, 2016. (Photo by Basem Ayoubi/Imageslive/ZUMA Press/Splash News)

A walruses at Hagenbeck Zoo in Hamburg, Germany on July, 7, 2015. (Photo by Werner Struss/Startraks action)

Women practice yoga during a performance on a glass bridge at the Shiniuzhai National Geo-park in Pingjiang county, Hunan province, China, November 5, 2015. About hundred yoga fans put on the show to promote the concept of green life and the idea of harmony between human and nature on Thursday, according to local media. (Photo by Reuters/China Daily)

Rick Sorenson, owner of the Rio Ramaza Marina, wades in the Sacramento River after securing an old paddlewheel boat on his property as the river makes its way up the levee on Garden Highway in Sacramento, Calif., Monday, January 9, 2017. (Photo by Hector Amezcua/The Sacramento Bee via AP Photo)

“Touring the Koko-en Gardens adjacent to the Himeji castle was an unexpected highlight of our visit”, wrote Jeff Solar, 64, of Silver Spring, Md., about his trip to Japan. “The fall colors were outstanding and the gardens were both amazing and a bargain (just a few Yen added to the cost of the Himeji Castle admission)”. (Photo by Jeff Solar/2017 Washington Post Travel Photo Contest)

“Joey”, a dwarf Siamese rabbit, is dressed as Batman's sidekick Robin at a Halloween dog costume parade and contest in Long Beach, California, October 28, 2012. (Photo by Robyn Beck/AFP Pfoto)

American actress Nicola Peltz poses on the red carpet as she arrives for the world premiere of the movie “Transformers 4: Age of Extinction” in Hong Kong Thursday, June 19, 2014. The latest installment in the blockbuster series of “Transformers” films is making its world premier not in the usual entertainment hubs of Los Angeles or New York but in the wealthy Chinese metropolis of Hong Kong, the latest sign of Hollywood's increasing focus on China's booming film market. (Photo by Kin Cheung/AP Photo)