These greenfinches go head to head in what appears to be a heroic fight or a playfull moment together, inspiration for a new version of “Angry Birds”, in Trezzo Sull'Adda, Italy in March 2013. (Photo by Marco Redaelli/IMP/AbacaPress.com)

A woman takes a photograph of a sculpture titled “Couple Under an Umbrella, 2013” by Australian sculptor Ron Mueck during a preview of his exhibition at the Pinacoteca Museum in Sao Paulo November 19, 2014. (Photo by Nacho Doce/Reuters)

Members of the Coney Island Polar Bear Club warm up before swimming at the beach at Coney Island in New York, December 15, 2013. (Photo by Eric Thayer/Reuters)

Kent Josephso organizes his 8mm tracer rounds during the Big Sandy Shoot in Mohave County, Arizona March 23, 2013. The Big Sandy Shoot is the largest organized machine gun shoot in the United States attended by shooters from around the country. Vintage and replica style machine guns and cannons are some of the weapons displayed during the event. Picture taken March 22, 2013. (Photo by Joshua Lott/Reuters)

A boy poses with a butterfly on his face during a photocall to promote the “Sensational Butterflies” exhibition at the Natural History Museum in central London, on March 25, 2013. With around 400 live tropical butterflies and moths living in the temporary facility, visitors will get the chance to see them flying freely as well as looking for emerging butterflies at the hatchery window. Running from March 29 to September 15, 2013, the exhibition is housed in a structure in the museum grounds. (Photo by Leon Neal/AFP Photo)

An RAF Eurofighter EF-2000 Typhoon takes off on March 22, 2011 at the Gioia Del Colle airbase in Italy. After last week's UN resolution which voted for a non-fly zone to be enforced over Libya, sorties have continued to be flown by forces representing the UN coalition from Italian military bases. More than 110 missiles have been fired on pro-Gaddafi strongholds in attempt to knock out the Libyan leaders defences.

A large variety of weapons were for sale at the Washington County Fairgrounds Gun Show that drew thousands of people over the weekend, on March 22, 2013. (Photo by Gary Porter)

A model presents a hairstyle during the 7th international festival of hairdressing art, fashion and design called “Crystal Angel” in Kiev, Ukraine, on April 18, 2013. (Photo by Gleb Garanich/Reuters)