Two Herens cows lock horns during the qualification round of the annual “Battle of the Queens” cow fight finals in Aproz, in the western Alpine canton of Valais May 5, 2013. Each year when taken to the alpine pastures, the cows test their strength and fight for the herd's leadership. The competition continues until a new queen has forced all the other cows to retreat. (Photo by Valentin Flauraud/Reuters)

Peru, Iquitos. Restaurant in Bellavista, an area by the Amazon on April 2005. (Photo by Jean-Claude Coutausse)

Models wait backstage during the Ukrainian Fashion Week in Kiev, October 16, 2015. (Photo by Valentyn Ogirenko/Reuters)

Female Siberian tiger Dasha yawns in the new enclosure at the zoo in Duisburg, Germany, 30 March 2016. The new facility is three times larger than the old one and will be opened to the public on the same day. (Photo by Roland Weihrauch/EPA)

A man standing on the first cables during the construction of the Golden Gate Bridge with the Presidio and San Francisco in the background, San Francisco, California, 1935. (Photo by Underwood Archives/Getty Images)

A tea garden worker plucks tea leaves inside Aideobarie Tea Estate in Jorhat in Assam, India, April 21, 2015. Unrest is brewing among Assam's so-called Tea Tribes as changing weather patterns upset the economics of the industry. Scientists say climate change is to blame for uneven rainfall that is cutting yields and lifting costs for tea firms. (Photo by Ahmad Masood/Reuters)

A chicken seller carries his chickens on his head in the market in Peshawar, Pakistan, August 20, 2015. (Photo by Khuram Parvez/Reuters)

Revelers march in the Lower Ninth Ward during a second line parade marking the 10th anniversary of Hurricane Katrina on August 29, 2015 in New Orleans, Louisiana. (Photo by Mario Tama/Getty Images)