Bosnian men urge their horses to pull logs up a hill during a competition in the Bosnian town of Sokolac 50 kms west of Sarajevo, Bosnia,on Monday, April, 13, 2015. The annual festival celebrates the centuries old tradition of pulling logs honoring the owners of the strongest horses. Owners of the horses gather from all over Bosnia and beyond, and compete in a show of horse strength. (Photo by Amel Emric/AP Photo)

A baby giant panda plays at Chengdu Research Base of Giant Panda Breeding in Chengdu, Sichuan province, China, January 22, 2017. (Photo by Jason Lee/Reuters)

Haitians dressed in costumes dance during the Haitian National Carnival in Jacmel, Haiti, 19 February 2017. Locals and foreigners gathered to enjoy the colorful carnival in which parades are full of art, music and dance. (Photo by Bahare Khodabande/EPA)

In this Sunday, March 12, 2017, picture a Don Sphinx cat reaches for a judge while being evaluated, in Bucharest, Romania. More than 1,500 dogs and 150 cats from twelve countries were evaluated during a three day pet show and competition in the Romanian capital. (Photo by Vadim Ghirda/AP Photo)

A woman takes part in a traditional horse parade through the streets of San Jose, Costa Rica December 26, 2015. Thousands of riders participated in the parade, which is part of annual year-end festivities. (Photo by Juan Carlos Ulate/Reuters)

Photographer Andy Hall joins the thousands of fans from west Africa who have gathered for Baaba Maal's annual Blues du Fleuve festival in Senegal. Here: Dancers wait to perform on stage. (Photo by Andy Hall/The Observer)

Photojournalist Lauren DeCicca met three Thai families who have created makeshift homes from abandoned aeroplanes in a vacant lot in east Bangkok. This vacant lot on Ramkhamhaeng Road in east Bangkok is locally known as the “Airplane Graveyard”. Here: A child perches in one of the fuselages. (Photo by Lauren DeCicca/The Guardian)

Members of security forces secure Tahrir Square in Cairo, Egypt, November 11, 2016. Egypt imposed a big security clampdown in its cities on Friday as mass demonstrations called to protest against austerity measures failed to take place. Riot police and armored vehicles filled the otherwise empty streets of central Cairo, but most people stayed at home. (Photo by Mohamed Abd El Ghany/Reuters)