In this undated photo made available by journal Nature on January 15, 2014, a northern bald ibis (Geronticus eremita) flies in Tuscany, Italy. A new study released Wednesday, January 15, 2014 says the birds choreograph the flapping of their wings, getting a boost from an updraft of air in the wake of the flapping wings by flying behind the first bird and off to the side. When a flock of birds take advantage of these aerodynamics, they form a V. (Photo by Markus Unsöld/AP Photo)

Austrian artist Erwin Wurm (R) stands next to an extra of his participation sculpture “Hose lueften, Haende hoch” (air out pants, hands high) at the garden of the Staedel Museum, in Frankfurt am Main, Germany, 06 May 2014. The series “Wurm: One Minute Sculptures” include painted or written instructions tell the person what they have to do and where for 60 seconds. The exhibition runs from 07 May to 13 July. (Photo by Arne Dedert/EPA)

A German Air Force Officer sits astride a dead boar outside a house where he is stationed near the Western Front, in this 1918 handout picture. This picture is part of a previously unpublished set of World War One (WWI) images from a private collection. The pictures offer an unusual view of varied and contrasting aspects of the conflict, from high tech artillery to mobile pigeon lofts, and from officers partying in their headquarters to the grim reality of life and death in the trenches. The year 2014 marks the centenary of the start of the war. (Photo by Reuters/Archive of Modern Conflict London)

These stunning pictures show a normally vicious tiger calmly swimming in a pool of algae, on Jule 9, 2014. The powerful cat takes a refreshing break by taking a dip in the bright green algae. But it looks like this big cat is scared of getting his head wet as he strains to keep it above the water. After splashing around for a bit the tiger gets out and tries to air-dry with specks of the vegetation dripping off his fur. The striking pictures were taken at Copenhagen zoo by snapper Soren Lundgren Neilson. (Photo by Soren Nielsen/Caters News)

A handout picture taken and released by the British Ministry of Defence (MOD) on March 25, 2024 shows humanitarian aid being airdropped over Gaza from a RAF A400M aircraft The Royal Air Force airdropped over 10 tonnes of food supplies into Gaza for the first time on Monday, as part of international efforts to provide life-saving assistance to civilians. The aid consists of water, rice, cooking oil, flour, tinned goods and baby formula. (Photo by Leah Jones/MOD/AFP Photo)

This picture taken on October 22, 2024 shows South Korean shooter Kim Ye-ji posing for a photo during an interview with AFP at a shooting range in Seoul. Kim, 32, won silver in the women's 10m air pistol at this summer's Paris Olympics and captured the internet's attention with her nonchalant cool. But she told AFP that she fell into her sport by accident. (Photo by Jung Yeon-je/AFP Photo)

RAF Tornados fly above the Lossiemouth air base on March 18, 2011 in Lossiemouth, Scotland. UK defence forces will help to enforce a no-fly zone over Libya after the UN voted in favour of a resolution that backed 'all necessary measures', except a foreign occupation force, to protect Libyan civilians.

A fan lies passed out on the first day of the Wacken Open Air heavy metal music fest on August 4, 2011 in Wacken, Germany. Approximately 75,000 heavy metal fans from all over the world have descended on the north German village of 1,800 residents for the annual three-day fest. (Photo by Sean Gallup/Getty Images)