The six-months-old female koala cub holds on to the back of zoo keeper Lena at the zoo in Duisburg, Germany, 23 October 2015. The yet unnamed baby weighs 580 grams. (Photo by Roland Weihrauch/EPA)

Chinelos (traditional costumed dancers) perform in front of San Andres Ocotlan church as part of continuing festivities to welcome the new year in Calimaya, Mexico on January 4, 2016. (Photo by Arturo Hernandez/Demotix/Corbis)

In this Sunday, March 2, 2014 photo, animal barber Mohamed Mahmoud shaves a customer's initials onto the rump of a donkey in Cairo, Egypt. Clients typically request for regular trims to keep animals cool in the summer, initials in English letters, and patterns – but sometimes they give Mahmoud full creative license. (Photo by Maya Alleruzzo/AP Photo)

Macaque monkeys crowd together in their cage at a monkey farm on February 3, 2016 in Xinye county, Henan province, China. The area boasts a centuries-long and lucrative history of raising and training monkeys for performance. In Xinye, villagers are seeing an increase in business with the lunar calendar's “Year of the Monkey”. Farmers say most of the monkeys are bred and raised for domestic zoos, circuses, and performing groups, but add that some are also sold for medical research in China and the United States. Despite the popularity of the tradition, critics contend the training methods and conditions constitute animal cruelty. (Photo by Kevin Frayer/Getty Images)

Indian children work nearby to their parents at a construction project in front of the Jawaharlal Nehru Stadium on January 30, 2010 in New Delhi, India. The children accompany their parents to the work site, where if they are prepared to work, they will receive money for bread an milk and be provided with dinner by the contractor. The sheer scale of the project has drawn an enormous population of migrant workers from all over India.

Syrians gather during an evacuation operation of rebel fighters and their families from rebel-held neighbourhoods on December 15, 2016 in the embattled city of Aleppo. A convoy of ambulances and buses left rebel territory in Aleppo in the first evacuations under a deal for opposition fighters to leave the city after years of fighting. The rebel withdrawal will pave the way for President Bashar al-Assad's forces to reclaim complete control of Syria's second city, handing the regime its biggest victory in more than five years of civil war. (Photo by Karam Al-Masri/AFP Photo)

A man carries a woman across a river at Petit Goave where a bridge collapsed during the rains of the Hurricane Matthew, southwest of Port-au-Prince, October 5, 2016. (Photo by Hector Retamal/AFP Photo)

President Barack Obama with does the tango with a dancer during the State Dinner at the Centro Cultural Kirchner, Wednesday, March 23, 2016, in Buenos Aires, Argentina. (Photo by Pablo Martinez Monsivais/AP Photo)