Roof-topping enthusiast Daniel Lau takes a selfie with high-rise buildings down below as he stands on the top of a skyscraper in Hong Kong, China on August 15, 2017. A craze that began in Russia has now taken hold in Hong Kong, one of the world's most vertical cities. Mr Lau said he had been inspired by Russian climbers and that he was unafraid of the vertiginous heights he scales. (Photo by ImagineChina/Rex Features/Shutterstock)

Members of the Women's Organization to War on Styles (WOW) picket a dress shop in Berkeley, Calif., August 23, 1947, in protest to longer skirts and padded hips. They are the wives of GI students at the University of California. Left to right: Jackie Houser; Wanda Ames; Dorothy Inman; Terry Ligon; Ruth Van Arkel; Carrol Reynolds, and Barbara Carmichael. (Photo by AP Photo)

Cave Diver, Anhumas Abyss, Bonito, Brazil: The Anhumas Abyss is an underground cavern with a crystal-clear lake below, more than 260 feet (79 m) deep. A visitor must enter through a narrow opening at the top of the chamber and rappel into the cave. Snorkeling and scuba diving in the lake reveal amazing scenery. Distinctive, conical limestone stalagmites and stalactites occupy the lake and the surrounding area, some reaching 65 feet (20 m) high. (Photo by Marcio Cabral/Nature’s Best Photography Awards 2017)

A man transports the carcass of a car on a two- wheeled carriage in a neighborhood in Abobo, a suburb of Abidjan, Côte d’Ivoire on December 1, 2017. (Photo by Issouf Sanogo/AFP Photo)

Actress Sophia Loren teases the hair of critic Gene Shalit in New York, Tuesday, February 20, 1979. During the filming of a segment for the NBC television “Today” show. In the background is a large photograph of Miss Loren. The segment is scheduled for airing later this week. (Photo by Dave Pickoff/AP Photo)

Racegoers during Ladies Day of the 2018 Cheltenham Festival in Cheltenham, England on March 14, 2018. (Photo by Graham Stone/Rex Features/Shutterstock)

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)

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)