A dog jumps over an obstacle during the International Agility Riga Cup competition in Riga, Latvia, August 15, 2015. (Photo by Ints Kalnins/Reuters)

Revellers watch as police officers dance in the street at the Notting Hill Carnival in west London, August 30, 2015. (Photo by Toby Melville/Reuters)

A reveler jumps over a bonfire during the night of San Juan in Alcobendas near Madrid, Spain, Wednesday, June 24, 2015. The San Juan night coincides with the Summer solstice and it's the welcome to Summer. This celebration takes place during the shortest night of the year in almost all cities and towns of Spain. (Photo by Andres Kudacki/AP Photo)

An incredible clear-air lightning display from storms to the east of Noonamah, just outside Darwin on April 6, 2015. (Photo by Jacci Ingham/The Guardian)

A worker stack bricks on his head at a brick factory in Lalitpur January 12, 2015. (Photo by Navesh Chitrakar/Reuters)

Cats gather in front of a house damaged by shelling in the town of Dokuchayevsk, south of Donetsk, February 12, 2015. (Photo by Maxim Shemetov/Reuters)

An artist draws a tattoo on a woman's arm during a tattoo convention in Ljubljana April 18, 2015. (Photo by Srdjan Zivulovic/Reuters)