An Indian Muslim worker applies colors on Kalavas (sacred threads) in Ajmer in the Indian state of Rajasthan on May 24, 2018. (Photo by Himanshu Sharma/AFP Photo)

An Indian labourer carries a sack of plastic bottles on his head near one of the largest disposal sites in north-east India, ahead of the “World Environment Day” in Boragaon area of Guwahati on June 4, 2018. World Environment Day is marked annually on June 5, and aims at promoting awareness and action to protect the environment. (Photo by Biju Boro/AFP Photo)

Prince Philip, Duke of Edinburgh practicing his bicycle polo technique, Windsor Great Park, Berkshire, 1964. (Photo by Norman Potter/Daily Express/Hulton Archive/Getty Images)

Pablo Picasso, famed 66-year-old Spanish artist who has lived most of his life in France, suns himself on a boat on the beach at Golfe Juan in Vallauris on the French Riviera on March 10, 1948. Entering a new period in his varied artistic career, Picasso has turned to painting pottery at the nearby town of Vallauris. (Photo by AP Photo)

Evangelia Platanioti of Greece competes in the Solo Technical Routine at the Glasgow 2018 European Synchronised Swimming Championships, Glasgow, Britain, 06 August 2018. (Photo by Neil Hall/EPA/EFE)

Two Czech Gripen fighter planes demonstrate a flight interception of a Belgian air force transport plane over the Czech Republic, as part of NATO drills on September 12, 2018. (Photo by Francois Lenoir/Reuters)

In this August 24, 2018 photo, Changlair Aristide pauses for a portrait, wearing his protective clothing, including an old U.N. peacekeeper's jacket he found in the trash, before scavenging the Truitier landfill in the Cite Soleil slum of Port-au-Prince, Haiti. Before 2004, Aristide recalled having enough money to splurge on shoes, T-shirts and pants, but this year he could not buy his kids anything new for the school year. “Life is like that, up and down”, Aristide said. “They'll go to school anyway, even if I have to sell my pig. I love them”. (Photo by Dieu Nalio Chery/AP Photo)

Bloodthirsty by Thomas P. Peschak, Germany/South Africa — winner, Behaviour: birds. When rations run short on Wolf Island, in the remote northern Galápagos, the sharp-beaked ground finches become vampires. Their sitting targets are Nazca boobies and other large birds. The finches rely on a scant diet of seeds and insects, which regularly dries up, so they drink blood to survive. ‘I’ve seen more than half a dozen finches drinking from a single Nazca booby,’ says Tom. Rather than leave their nests the boobies tolerate the vampires, and the blood loss doesn’t seem to cause permanent harm. (Photo by Thomas P. Peschak/2018 Wildlife Photographer of the Year)