A baby rhesus macaque (Macaca mulatta) looks up as it plays with a tiger cub at a zoo in Hefei, Anhui province, August 2, 2012. (Photo by Jianan Yu/Reuters)

Women Wrestlers, Bolivia. Lucha libre (Bolivian wrestling) is one of the most popular sports in the country. Women wrestlers are known as cholitas and have in the last ten years become popular in the sport. Here, Carmen Rosa and Yulia la Pacena perform in a benefit show to raise money for the bathrooms of a school in La Paz, Bolivia, 26 June 2011. (Photo by Daniele Tamagni)

Egmont National Park in New Zealand with Mt. Taranaki at its center is seen in a Landsat 8 satellite image taken July 3, 2014 and released by NASA November 14, 2014. The image is from the book “Sanctuary: Exploring the World's Protected Areas from Space”, published by the Institute for Global Environmental Strategies with support from NASA, which was released this week. (Photo by Reuters/NASA/USGS)

An employee walks past a rotary dredge working at an open-cast iron ore mine of the Stoilensky mining and concentration plant (GOK), owned by the Novolipetsk (NLMK) steel mill, in the city of Stary Oskol in Belgorod region, Russia, August 4, 2015. (Photo by Maxim Shemetov/Reuters)

Young female Ibex on the fork of Disteis (2,200 m), near the top of the Jof di Montasio (Friuli, Italy). (Photo by Stefano Zocca)

A staff interacts with a white lioness in a private zoo called “12 Months” in the town of Demydiv, Ukraine, January 13, 2016. (Photo by Gleb Garanich/Reuters)

A Somali fisherman carries a fish from his vessel on the shores of the Indian Ocean on Liido beach, in Mogadishu, Somalia November 4, 2016. (Photo by Feisal Omar/Reuters)

A customer buys a box of bullits and a target of Osama Bin Laden October 3, 2001 at Blue Ridge Arsenal in Chantilly, VA. Guns sales have risen across America since the September 11th terrorist attacks. (Photo by Mark Wilson/Getty Images)