An Afghan refugee girl shows her younger brother a calf in a slum on the outskirts of Islamabad, Pakistan, Friday, February 6, 2015. (Photo by Muhammed Muheisen/AP Photo)

In this photo taken on Wednesday, February 17, 2016, a volunteer fighter with the Syrian Government forces sits atop a tank in the province of Raqqa, Syria. In recent weeks, Syrian government forces captured dozens of villages and towns across the country. (Photo by Alexander Kots/Komsomolskaya Pravda via AP Photo)

Lulu, her Playa name, falls into a foam pit as approximately 70,000 people from all over the world gather for the 30th annual Burning Man arts and music festival in the Black Rock Desert of Nevada, U.S. September 1, 2016. (Photo by Jim Urquhart/Reuters)

Children feed a giraffe at Pairi Daiza wildlife park, a zoo and botanical garden in Brugelette, Belgium, May 25, 2015. (Photo by Francois Lenoir/Reuters)

Young revelers take part in a parade called "La Calabiuza" on November 1, 2015, on the eve of the Day of the Dead in Tonacatepeque, 20 kms (13 miles) north of San Salvador. During the celebration, the residents of Tonacatepeque, originally an indigenous community, recall the characters from the mythology of Cuscatlan – pre-Columbian west and central regions of El Salvador – and their dead relatives. (Photo by Marvin Recinos/AFP Photo)

Military items for women are seen in a store in Erbil, Iraq January 24, 2017. (Photo by Marius Bosch/Reuters)

Rebecca Bailey rides a unicycle during a winter nor'easter snow storm in Boston, Massachusetts, U.S. February 9, 2017. (Photo by Brian Snyder/Reuters)

Porters carry the carcasses of a shark (L) and a Marlin (R) to the local market in Hamarweyne near the port of Mogadishu on the Indian Ocean coast on November 18, 2014 in the Somalia capital as fishermen bring in their catch. (Photo by Mohamed Abdiwahab/AFP Photo)