Deers walk past Indonesia's honour guard as they wait for the arrival of Saudi Arabia's King Salman bin Abdul Aziz at the presidential palace in Bogor on March 1, 2017. Cheering crowds welcomed King Salman on March 1 as he began the first visit by a Saudi monarch to Indonesia for almost 50 years, seeking stronger economic ties with the world's most populous Muslim-majority country. (Photo by Adek Berry/AFP Photo)
A hippopotamus is sprayed with water on a hot summer day at Anna National Zoological Park in Chennai, India on April 26, 2017. (Photo by Arun Sankar/AFP Photo)
The coendou porcupine couple 'Joppi' (L) and 'Fletcher' nibble at a vegetables in their enclosure at the zoo in Frankfurt am Main, Germany, 03 December 2015. Coendou porcupines are nocturnal rodents related to porcupines and guinea pigs and native to the rain forests of Central and South America as well as Trinidad. (Photo by Arne Dedert/EPA)
Students exercise in body training at Bishan Vocational Education Center in Chongqing, southwest China, January 13, 2016. These students were trained to be stewardesses of the high-speed train. (Photo by Xie Jie/Xinhua)
A polar bear cub, born on November 26, 2014, and its mother Flocke spend time outdoors on March 9, 2015 at the Marineland animal exhibition park in the French Riviera city of Antibes. AFP PHOTO / VALERY HACHE (Photo credit should read VALERY HACHE/AFP/Getty Images)
A moon appears behind a windmill a day before the supermoon is full on September 8, 2014 in Consuegra, in Toledo province, Spain. Consuegra belongs to a region made famous by the novel “Don Quijote de la Mancha” (Don Quixote) writed by Miguel De Cervantes. Some of the windmills belong to the 16th century. (Photo by Pablo Blazquez Dominguez/Getty Images)
Youths parade wearing World War Two uniforms during the Independence Day celebrations in Gdansk November 11, 2014. (Photo by Lukasz Glowala/Reuters/Agencja Gazeta)