Behaviour winner; Courting Royals: two royal terns in courtship display by Kristian Bell. Another beautiful morning on a beautiful beach on the Gulf Coast of Florida seemed to prompt these two royal terns to commence an intricate courtship dance. The photograph was taken with a Canon 300mm lens and 2x extender. (Photo by Kristian Bell/Deakin University/Royal Society Publishing Photography Competition 2018)

No. 10: Sphynx. A suede-like coat is the sphynx's most unmistakable feature, but he's also curious, smart and a clown who craves applause for his antics. In fact, he loves attention so much that you may want to consider getting him a fellow sphynx playmate. (Photo by Quentin Descotte)

Dr. P.A. Smithe was sent by the American Red Cross as a doctor and surgeon to work at a hospital in Vienna. He sailed to Europe in December 1915 and returned home in August 1916, according to his daughter, who donated his images to the National World War I Museum. Photo: Turkish army, including cavalry, infantry and artillery. (Photo by Dr. P.A. Smithe/National World War I Museum, Kansas City, Mo.)

Kanphitcha Sungsuk, 21, (C), lines up with young men to speak to officers during an army draft held at a school in Klong Toey, the dockside slum area in Bangkok, Thailand, April 6, 2017. Thailand is widely seen as a paradise for gay and transgender people, but many complain of being treated as second-class citizens and the obligation to respond to the draft can be a nightmare when they turn 21. (Photo by Athit Perawongmetha/Reuters)

Dancers Marion Krebs and Judy Ness, right, pose as batter and catcher in front of the Chicago White Sox dugout before start of game with Detroit at Comiskey Park, Chicago, Ill., September 18, 1959. White Sox won, 1-0, to move within two games of clinching the American League pennant. (Photo by AP Photo)

A passenger (L) gets inside a decorated matatu as other passengers wait for it to fill at night in the streets of Nairobi, Kenya, 24 March 2018. The Matatu culture is very big in Kenya, the minibuses are decorated with colorful graffiti inside and outside and most of them are equipped with TV screens, high-speed internet, and power sockets. (Photo by Daniel Irungu/EPA/EFE)

Nopparat (R), a 24-year-old transgender, and a Buddhist monk (L) wait to speak to officers during an army draft held at a school in Bang Na in Bangkok April 3, 2015. Thai men over 21 must serve in the army. Those who volunteer serve six months, but others choose the annual lottery, which goes on for 10 days in recruitment centres around Thailand. Only those not considered physically capable of service, the mentally ill and those who have significantly altered their physical appearance, such as transgenders, are exempt. Picture taken April 3, 2015. (Photo by Athit Perawongmetha/Reuters)

This is the incredible moment a fierce lightning bolt crashed against the Grand Canyon illuminating the steep canyon walls. Shrouded in darkness, the breath-taking landscape was shocked into life as mother nature sent the bolt storming down to Earth. As it cracked against the rocks the bright blue bolt illuminated the South Rim of the canyon, considered one of the Seven Natural Wonders of the World. With just the Desert View Watchtower in the foreground, the lightning was perfectly framed by the canyon which is located in Arizona, USA. (Photo by Travis Roe/U.S. Dept. of the Interior/Caters News)