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)

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)

A woman sticks out her tongue as she shops at the Quinta Crespo street market in downtown Caracas, Venezuela, Saturday, January 26, 2019. The country's political showdown moves to the United Nations Saturday where a Security Council meeting called by the United States will pit backers of President Nicolas Maduro against the Trump administration and supporters of the country's self-declared interim leader Juan Guaido. (Photo by Rodrigo Abd/AP Photo)

Sun Rongchun, 57, exercises with an improvised cervical traction device attached to a high bar at a sports complex in Shenyang, Liaoning province, China on April 9, 2019. (Photo by Sheng Li/Reuters)

An Indian Sadhu, or Hindu holy man, performs a yoga position on International Yoga Day at Kamakhya temple in Gauhati, India, Friday, June 21, 2019. (Photo by Anupam Nath/AP Photo)

A Saudi woman holds a falcon as she participate for the first time in the 2nd Saudi Falcons and Hunting Exhibition in Riyadh, Saudi Arabia on October 16, 2019. (Photo by Ahmed Yosri/Reuters)

Female members of the Hammer tribe from the village of Turmi, situated in southern Ethiopia near the Kenyan border, dance as part of a ritual called the “bull jumping ceremony” that takes place during the passage of a young boy to adulthood, in Turmi, Ethiopia, 25 September 2019. (Photo by Stéphanie Lecocq/EPA/EFE)

An Indigenous schoolchild dressed in traditional attire takes part in a rally to commemorate Indigenous Resistance Day in Catarina town, Nicaragua October 12, 2016. This holiday coincides with Columbus Day which commemorates Christopher Columbus landing in America in 1492. But rather than celebrating the discovery of the Americas, the Nicaraguans observe Indigenous Resistance Day to celebrate the bravery of the indigenous population in the fight against the Spanish conquistadors. (Photo by Oswaldo Rivas/Reuters)