A man sledges on Primrose Hill with his daughter and their dog on February 5, 2012 in London, England. The United Kingdom is experiencing heavy snowfall with many areas affected. (Photo by Peter Macdiarmid/Getty Images)

A replica of an ice age lion is seen during the “Giganten Der Eizeit” exhibition opening on May 31, 2011 in St Peter-Ording, Germany. Europes biggest ice age exhibition opens on 3rd of June. (Photo by Krafft Angerer/Getty Images)

Penny Farthing cyclists ride near Tower Bridge on June 9, 2011 in London, England. The riders have cycled from Paris ahead of the IG Markets London Nocturne cycling event on June 11, 2011. (Photo by Peter Macdiarmid/Getty Images)

Twenty five life-size donkeys have been given pride of place in St Paul's Cathedral as part of an interfaith exhibition. They've been painted by Egyptian and Western artists, to show solidarity for the people of Egypt. Photo: Artist painted donkey statues are displayed in the “Caravan” exhibition on August 30, 2013 in London, England. (Photo by Peter Macdiarmid)

A passenger plane comes into land over a field containing horses at Heathrow Airport on August 11, 2014 in London, England. Heathrow is the busiest airport in the United Kingdom and the third busiest in the world. The airport's operator BAA wants to build a third runway to cope with increased demand. (Photo by Peter Macdiarmid/Getty Images)

Miss Zero, whose real name is Sasha Frolova, of Russia celebrates winning the Alternative Miss World contest at Shakespeare's Globe theatre in London, October 18, 2014. The competition, which is open to entrants of any gender or nationality, was started by artist Andrew Logan in 1972. (Photo by Peter Nicholls/Reuters)

A visitor walks on a giant chalk artwork called “Wasting Time” at the Chalk Urban Arts Festival in Sydney on October 25, 2014. The picture is the biggest 3-D artwork created in Australia by two artists, Leon Keer from Holland and Jenny McCracken from Australia. (Photo by Peter Parks/AFP Photo)

Italian police officers carry away a FEMEN activist during a protest in St. Peter's Square at the Vatican, Friday, November 14, 2014. Members of the Ukrainian feminist group Femen staged a protest against the upcoming visit of Pope Francis at the European Parliament and Council. (Photo by AP Photo)