An alpaca chewing a leaf is pictured on November 18, 2014 in the zoo of Frankfurt am Main, Germany. (Photo by Frank Rumpenhorst/AFP Photo/DPA)

Indonesian child jockey Egi, 8, poses for photographs as he participates in a traditional horse race marking Indonesia's 70th independence anniversary, in Bima, West Nusa Tenggara province, Indonesia, 08 August 2015. Horse racing is the traditional sport in the area and a cultural heritage which continues to be preserved by the people of Bima, a small city on the east side of Sumbawa island. Similar races also held in Sumbawa Besar regency and Dompu regency. (Photo by Mast Irham/EPA)

16-year-old panda, Ye Ye, rests in an enclosure at the Wolong Nature Reserve, a conservation center that trains pandas for release into the wild. This image was published in the August 2016 National Geographic magazine as part of the “Pandas Gone Wild” story. (Photo by Ami Vitale/National Geographic Creative)

Behaviour: Mammals category. Giant Gathering by Tony Wu, USA. Dozens of sperm whales mingled noisily off Sri Lanka’s northeast coast, stacked as far down as Tony could see. This was a congregation of dozens of social units, like a gathering of the clans. Aggregations like this could be a critical part of the whales’ rich social lives but are rarely reported. Some two thirds of the population was wiped out before commercial whaling was banned in 1986. This kind of major gathering could be “a sign that populations are recovering”, says Tony. (Photo by Tony Wu/Wildlife Photographer of the Year 2017)

Bella Hadid is close to losing her top while on location for a photoshoot in Brooklyn, New York on December 11, 2017. (Photo by NPEx/Splash News and Pictures)

An African giant pouched rat sniffs for traces of landmine explosives at APOPO's training facility in Morogoro on June 17, 2016. APOPO trains the rats to detect both tuberculosis and landmines at its facility. Every year landmines kill or maim thousands of people worldwide. The trained rats sniff for explosive and so are able to detect the presence of landmines far faster than conventional methods which involve metal detection. (Photo by Carl De Souza/AFP Photo)

A Peru fan cheers of her team during a Quarterfinal match between Colombia and Peru at MetLife Stadium as part of Copa America Centenario US 2016 on June 17, 2016 in East Rutherford, New Jersey, US. (Photo by Chris Szagola/LatinContent/Getty Images)

Workers clean empty cooking oil containers at a roadside recycling workshop in Kolkata, India, July 13, 2016. (Photo by Rupak De Chowdhuri/Reuters)