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)

Spectators pose for a selfie before the running of the Melbourne Cup at the Flemington Racecourse in Melbourne, Australia, Tuesday, November 6, 2018. (Photo by Andy Brownbill/AP Photo)

A cat tries to find dry ground around an apartment complex in Houston after Hurricane Harvey hit on Aug. 30. Harvey made landfall in South Texas on August 25, leading to days of downpours that dumped more than 50 inches of rain. Harvey damaged or destroyed about 200,000 homes as the storm system flooded much of Houston and smaller coastal communities. (Photo by Scott Olson/Getty Images)

Two women kiss each other during a flashmob on the ocassion of the International Day Against Homophobia, Transphobia and Biphobia in Pamplona, Navarra, Spain, 17 May 2017. The International Day Against Homophobia, Transphobia and Biphobia is held every year on 17 May. (Photo by Villar Lopez/EPA/EFE)

Members of the Delirio dance company perform during the “Hechizo” (Spell) virtual show, inspired by the legend of the merry widow on Hallo​ween night, in Cali, Colombia, 31 October 2020. (Photo by Ernesto Guzman Jr./EPA/EFE)

A government employee reacts as she is sprayed with disinfectant before entering a government office building to curb the spread of COVID-19 on March 19, 2020 in Pasig city, Metro Manila, Philippines. The Philippine government has sealed off Luzon, the country's largest and most populous island, to prevent the spread of COVID-19. Land, sea, and air travel has been suspended, while government work, schools, businesses, and public transportation have been ordered shut in a bid to keep some 55 million people at home. The Philippines' Department of Health has so far confirmed 217 cases of the new coronavirus in the country, with at least 17 recorded fatalities. (Photo by Ezra Acayan/Getty Images)

Russian police cadets march during general rehearsal of the Victory Day parade on the Dvortsovaya Square in St. Petersburg, Russia, 07 May 2021. The military parade marking the 76th anniversary of the victory over Nazi Germany in the World War II will take place on the Dvortsovaya Square on 09 May 2021. (Photo by Anatoly Maltsev/EPA/EFE)