Employee Victoria Livesey walks past Banksy's “Kate Moss 2005” on display at Bonhams on March 23, 2012 in London, England. The painting, estimated at GBP 30,000 – 50,000, USD 48,000 – 79,000 and 35,000 – 59,000 euros forms part of the Urban Art Sale, which takes place at Bonhams on March 29, 2012. (Photo by Peter Macdiarmid/Getty Images)

Wellcome trust employee Zoe Middleton poses behind an artwork entitled “My Soul” by Katharine Dowson, which consists of a laser etched lead chrystal glass formation in the shape of a brain, and was created using the artists own MRI Scan, at Wellcome Collection on March 27, 2012 in London, England. (Photo by Dan Kitwood/Getty Images)

Mike De Butts adds the finishing touches to a giant Baobab Tree sculpture entitled “Under the Baobab”, outside the Southbank Centre on May 24, 2012 in London, England. The Pirate Technics' installation is made from a selection of brightly coloured fabrics from around the world, and is part of the Southbank Centre's “Festival of the World” exhibition, which includes a series of large scale pieces of art that will be in place around the Southbank centre over the Summer. (Photo by Dan Kitwood)

A Galapagos Tortoise shell is used as a foot rest at Heathrow Airport's Animal Reception Centre on January 25, 2011 in London, England. Many animals pass through the centre's doors ranging from exotic animals such as snow leopards and elephants, snakes and crocodiles, to the more common such as cats and dogs. In 2010 alone the centre processed approximately 10,500 cats and dogs, 1,300 birds, 105,000 day old chicks, 246,000 reptiles, 230 horses and 29 million fish. Most animals are part of zoo transfer schemes, the pet trade, or are pets in transit. (Photo by Dan Kitwood/Getty Images)

Assistant Manager Jayesh Vaghela brushes a vintage silk top hat at Lock & Co. Hatters on March 22, 2011 in London, England. Founded in St. James's in 1676, when Charles II was on the throne, this family owned business has provided hats for Royalty and the gentry for over 300 years. Staff report that sales of formal hats are booming ahead of the wedding of Prince William and Kate Middleton in Westminster Abbey on April 29, 2011.

Tim Klingender, Director of Aboriginal Art at Sotheby's hangs the painting “Emu Corroboree Man” by Clifford Possum Tjapaltjarri before a record auction of Aboriginal Art July 14, 2005 in Sydney, Australia. The painting is expected to fetch AUD 150,000 – 250,000 (USD 120,000 – 200,000). Sotheby's unveiled a selection of Aboriginal art and artifacts after a tour of New York and London, which will go to auction in Melbourne July 25 2005. The total pre-sales estimate of the collection is AUD 6 million – 8.5 million (USD 5 million – 7 million). (Photo by Ian Waldie/Getty Images)

A David Cameron look-alike poses with a polar bear model outside the Houses of Parliament as part of a Greenpeace protest on May 13, 2011 in London, England. The environmental charity Greenpeace arranged the protest to highlight the first anniversary of David Cameron’s speech when he pledged to make his new government the greenest ever. In April 2006 Mr Cameron traveled by huskie-drawn sledge when he visited the island of Svalbard in Norway to witness the effects of climate change. (Photo by Oli Scarff/Getty Images)

An employee of the British Museum examines a silver coin dating from 900 AD which is part of the Silverdale Viking Hoard on December 14, 2011 in London, England. The hoard, which was discovered by local metal-detectorist Darren Webster in North Lancashire, comprises of 201 silver objects including arm-rings, coins, finger-rings, ingots, brooch fragments and fine wire braid. (Photo by Oli Scarff/Getty Images)