An art installation formed with milk churns, made by land art artist Gerard Benoit a la Guillaume, is seen at the Chenau de Mayen in the resort of Leysin, Switzerland August 7, 2015. More than 80 milk churns were placed between the Tour d'Ai and the Tour de Mayen summits at an altitude of 2,000 meters (6,561 feet) above sea level under the direction of the artist, to be photographed for his ongoing art project entitled “Milk churns without borders”. (Photo by Denis Balibouse/Reuters)

Ireland's Philip Mulpeter, left, is kicked by Brazilian Vitor Nobrega during their welterweight mixed martial arts bout of International Pro Combat at the Estoril Casino in Estoril, near Lisbon, Portugal, Monday, January 26, 2015. Nobrega defeated Mulpeter. (Photo by Francisco Seco/AP Photo)

Going toe-to-toe, these fighting primates could give Floyd Mayweather a run for his money. The amazing images – captured by Australian tourist Julie Rathbone on the banks of the Zambezi river in Africa – show the pair engaging in a few fisticuffs. The Chacma baboons appeared to settle a disagreement by fighting – before a senior baboon plays referee and steps in to break it up. Nurse unit manager Julie Rathbone, 59, from New South Wales, was on a cruise down the river when she spotted the fracas unfolding. (Photo by Julie Rathbone/Caters News)

Revelers, covered in coloured powder, celebrate, during a Holi Run Festival in Madrid, Spain, Sunday, April 12, 2015. Thousands of revelers took part in the festival that includes a mini marathon. The festivals are fashioned after the Hindu spring festival Holi, which is mainly celebrated in the north and east of India. (Photo by Andres Kudacki/AP Photo)

A man watches as high surf crashes into the wall and spills onto Channel Drive in Montecito, Calif., January 7, 2016. Bacteria levels can increase significantly during and after rainstorms as contaminants in the runoff enter the ocean via storm drains, creeks and rivers. (Photo by Mike Eliason/AP Photo)

Members of the Gafatar sect walk in the rain as they evacuate their compound, which was later burned down by local villagers, in Antibar village, Mempawah Regency, Indonesia West Kalimantan Province, January 19, 2016 in this photo taken by Antara Foto. Local authorities and police moved the sect members to an army barracks located some 70 km (43 miles) away from Antibar for their safety following recent disputes between the sect and the villagers, Antara said on Tuesday. (Photo by Jessica Helena Wuysang/Reuters/Antara Foto)

A student activist is detained during a silent protest after Thailand's election commission filed charges against a group for posting “foul and strong” comments online criticising a military-backed draft constitution, in Bangkok, Thailand April 27, 2016. (Photo by Jorge Silva/Reuters)