Bangladeshi fisherman feed their otters as they catch fish in Narail some 208 kms from Dhaka on March 11, 2014. The fishermen are using a rare technique that relies on coordination between man and trained otters, a centuries-old fishing partnership that has already long died out in other parts of Asia. (Photo by Munir Uz Zaman/AFP Photo)

July 23, 2013 – Kampala, Uganda. Helene and Diana train daily more than 2.5 hours by Innocent Kapalata, a passionate and ambitious former boxer. Amidst the shanty homes a group of ambitious fighters are trying to reach for a better life. (Photo by Peter Bauza/ZUMA Press/VISUAL Press)

Culinary Specialist 2nd Class Jaqueline Rodriguez subdues a simulated suspect after being sprayed with oleoresin capsicum (OC) spray during security training aboard the amphibious dock landing ship USS Comstock (LSD 45). (U.S. Navy photo by Mass Communication Specialist 2nd Class Joseph M. Buliavac/Released). May 10, 2011

In this January 24, 2017 photo, boxer Idamerys Moreno wraps a bandage on her hand before a training session at a sports center in Havana, Cuba. Boxing has long been an athletic engine for Cuba, which has won 72 Olympic medals in that category but women are not allowed to box. (Photo by Ramon Espinosa/AP Photo)

A US Army M1A2 SEP tank participates in the Strong Europe Tank Challenge 2017 at the military training area in Grafenwoehr, Germany, 12 May 2017. Six North Atlantic Treaty Organization (NATO) nations and partner nations, Austria, France, Germany, Poland, Ukraine and the USA are taking part in this competing exercise. (Photo by Christian Bruna/EPA)

An exile Tibetan monk gestures as he makes a point in a dialectics debate with another monk, sitting right, at the Kirti monastery in Dharmsala, India, Monday, January 18, 2016. The debate is an essential part of their training as Buddhist monks. (Photo by Ashwini Bhatia/AP Photo)

An old locomotive train that was used for transporting coal is preserved as a monument at Ny-Alesund, in Svalbard, Norway, October 11, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. (Photo by Anna Filipova/Reuters)

A man carries his wife on his back as they make their way with their luggage along a flooded tunnel to catch their train, after heavy rainfall hit Jinhua, Zhejiang province, China, July 21, 2015. (Photo by Reuters/China Daily)