A Siberian tiger cub is seen at the Hengdaohezi Breeding Center for Felidae on October 26, 2007 in Harbin of Heilongjiang Province, China. Established in 1986, the breeding center is one of the world's largest captive breeding base for Siberian tigers. Distributed throughout northeastern China, far eastern Russia and North Korea, over 400 Siberian tigers exist in the wild, approximately 20 in China. (Photo by China Photos/Getty Images)

Men and Women dressed as zombies walk through Hyde Park on February 25, 2012 in Sydney, Australia. The annual Zombie Walk raises money for the Brain Foundation and this year teamed up with FX channel in promotion of “The Walking Dead” series premiering in Australia this weekend. (Photo by Brendon Thorne/Getty Images)

In this combination image visitors to the London Super Comic Convention dress as their favourite Marvel comic characters at ExCel on February 25, 2012 in London, England. Visitors to the Comic Convention are encouraged to wear a costume of their favourite character. (Photo by Peter Macdiarmid/Getty Images)

Migrating starlings fly in formation near the southern Israeli town of Rahat February 2, 2015. The phenomenon, known as murmuration, is most common during the winter months. (Photo by Nir Elias/Reuters)

Archie McQuater, 82-year-old clockmaker at Craiglea clocks, adjusts a clock face to British Summer Time (BST) on March 25, 2011 in Edinburgh, Scotland. Clocks will be put forward by one hour at 1:00 AM GMT on Sunday March 27, 2011 officially the start of British Summer Time. British Summer Time will end this year on October 30. (Photo by Jeff J Mitchell/Getty Images)

An Emperor Tamarin monkey, native to the Amazon rainforest, experiences its new home in the living rainforest enclosure at ZSL London Zoo on March 25, 2010 in London, England. Entitled “Rainforest Life” the large temperature and humidity controlled bio-dome is home to free-roaming monkeys, sloths, tree anteaters and tropical birds. The exhibit, which is opening in the International Year of Biodiversity, will be open to the public from March 27, 2010. (Photo by Oli Scarff/Getty Images)

A car stands in water on Ferry Road after two magnitude 6.0 and 5.5 earthquakes struck on June 13, 2011 in Christchurch, New Zealand. The aftershocks have followed four months after the major eathquake which hit the city on February 22, 2011 resulting in the deaths of 181 people. (Photo by Martin Hunter/Getty Images)

Activists protest against the upcoming visit of Pope Benedict XVI on the eve of his arrival on September 21,2011 in Berlin, Germany. A variety of groups, including the poltically left-wing as well as gay and lesbian rights advocates, partook in the demonstration. The Pope is scheduled to visit Germany from September 22–25. (Photo by Sean Gallup/Getty Images)