A woman, with her face covered with colored powders, dances during the Holi Festival of Colors in Lisbon, Sunday, September 15 2013. The festival, which is mainly celebrated during the Hindu spring festival Holi in some regions of India and Nepal, has become popular among people in other communities. (Photo by Francisco Seco/AP Photo)

Girls practice sit-ups during gymnastics lessons at the Shanghai Yangpu Youth Amateur Athletic School in Shanghai, China, on May 4, 2016. China's sports system has been enormously successful since the country returned to the Olympic fold in 1980, culminating with the host nation topping the medals' table at the 2008 Beijing Olympics. And yet, with the Rio de Janeiro Games less than three months away, the system is beginning to break down due to the shifting demographics of a more prosperous nation. (Photo by Aly Song/Reuters)

A giant river otter, the world's largest otter species, looks out of its enclosure at the newly completed River Safari in Singapore, on March 25, 2013. (Photo by Wong Maye-E/Associated Press)

A girl and boy carry a basket of fish in Kyaukpyu township, Rakhine state, Myanmar October 6, 2015. (Photo by Soe Zeya Tun/Reuters)

A mahout cleans the dust from his elephant in Ahmedabad, India, February 8, 2017. (Photo by Amit Dave/Reuters)

People dressed as zombies take part in a “Zombie Walk” parade in Athens, Greece, February 25, 2017. (Photo by Michalis Karagiannis/Reuters)

An Indian Hindu man dressed as Lord Shiva holds a lit candle in his mouth as he takes part in a religious procession ahead of the Maha Shivratri Festival in Jalandhar on February 22, 2017. Hindus mark the Maha Shivratri festival by offering special prayers and fasting to worship Lord Shiva, the lord of destruction. (Photo by Shammi Mehra/AFP Photo)

A guard secures gates of a catfish farm visited by a group of foreign reporters in Pyongyang, North Korea April 17, 2017. (Photo by Damir Sagolj/Reuters)