A Republican farmer defending a farm on the outskirts of Irun against Nationalist forces during the Spanish Civil War, 6th September 1936. A comrade lies dead by his side. (Photo by Keystone/Hulton Archive/Getty Images)

The Sphinx breed of cat “Adam vom Feisastern” of the German breeder Sabine Braeuer waits on a jury table during an annual International Pedigree Dog and Cat Show in Erfurt, Germany on June 10, 2012. (Photo by Jens Meyer/Associated Press)

In this picture made available Thursday July 11, 2013 a zoo-keeper presents three of twelve ferret babies at Eekholt Zoo in Grossenaspe, Germany, Wednesday July 10, 2013. The ferret babies were born May 25, 2013. (Photo by Markus Scholz/AP Photo/Dpa)

A man dressed as a zombie poses during the Thrill The World 2009 event, which sees fans from all over the world dance simultaneous to Michael Jackson's “Thriller” at Luna Park on October 25, 2009 in Sydney, Australia. (Photo by Brendon Thorne/Getty Images)

In this photograph taken on April 16, 2014, a veterinary staff member of the Sumatran Orangutan Conservation Programme center conducts medical examinations on a 14-year-old male orangutan found with air gun metal pellets embedded in his body in Sibolangit district in northern Sumatra island. (Photo by Sutanta Aditya/AFP Photo)

Three elephant seals put on a show in Roie Galitz's “Three Tanors”, taken on January 7, 2016 in South Georgia Island. The Comedy Wildlife Photography Awards are in full swing, so check out some of the fierce competitors jostling for the top prize this year. Photographers Paul Joynson-Hicks MBE and Tom Sullam founded the awards to spotlight wildlife conservation efforts and to inject some humour into the world of wildlife photography. (Photo by Roie Galitz/CWPA/Barcroft Images)

Situated in the Pacific Ocean some 620 miles (1,000 km) from the South American continent, these 19 islands and the surrounding marine reserve have been called a unique “living museum and showcase of evolution”. Photo: “Close-up. We had a juvenile Red-Footed Booby come visit us on the sun deck. I got some closeups with my ultrawide 11-16mm Tokina”. (Photo by Carl Fredrickson)

Carlos Boozer #5 of the Chicago Bulls grabs a rebound next to David West #30 of the New Orleans Hornets at the United Center on March 7, 2011 in Chicago, Illinois. The Bulls defeated the Hornets 85-77.