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)

Pakistani street performers sit around fire waiting for customers on a chilly evening in Rawalpindi, Pakistan, Wednesday, November 11, 2015. Some parts of Pakistan are facing a harsh winter. (Photo by B. K. Bangash/AP Photo)

Labourers break fast outside a shop in a market on the first day of the Muslim holy month of Ramadan in Karachi, Pakistan June 7, 2016. (Photo by Akhtar Soomro/Reuters)

An Egyptian street vendor carries plastic dishes on a street decorated for the holy month of Ramadan in old Cairo, Egypt June 1, 2016. (Photo by Amr Abdallah Dalsh/Reuters)

Pakistani passengers ride on crowded train returning from their hometown and villages after celebrating the Eid al-Fitr holiday to mark the end of the Muslim holy fasting month of Ramadan, to Lahore, Pakistan, Monday, July 11, 2016. (Photo by K.M.Chaudary/AP Photo)

Sellers sort persimmons for sale at a wholesale market in Hanoi, Vietnam October 3, 2016. (Photo by Reuters/Kham)

An internally displaced Afghan girl plays near their shelter at a refugee camp in Kabul January 13, 2015. (Photo by Omar Sobhani/Reuters)

An elephant enjoys its back being scrubbed by the keeper on March 1, 1950. (Photo by Fox Photos/Getty Images)