Two Herens cows lock horns during the qualification round of the annual “Battle of the Queens” cow fight finals in Aproz, in the western Alpine canton of Valais May 5, 2013. Each year when taken to the alpine pastures, the cows test their strength and fight for the herd's leadership. The competition continues until a new queen has forced all the other cows to retreat. (Photo by Valentin Flauraud/Reuters)

An orphaned rhesus monkey and white dove that seemed to have lost its mate forged a special bond at the Neilingding Island-Futian National Nature Reserve in China. The monkey was born on the island but had strayed from its mother. Luckily, it was taken in by work staff in the protection center and became friends with the pigeon that had lingered there after possibly losing its mate. (Photo by CNImaging/Photoshot)

“The last known individual of the subspecies was a male named Lonesome George (Spanish: El Solitario Jorge/George), who died on 24 June 2012. In his last years, he was known as the rarest creature in the world. George served as a potent symbol for conservation efforts in the Galápagos and internationally”. – Wikipedia. (Photo by Rodrigo Buendia/AFP)

An American family with a carved pumpkin illuminated by a candle to celebrate Halloween. (Photo by Sherman/Three Lions/Getty Images). Circa 1955

A collection of Sir Winston Churchill's wartime cigars, including four Romeo y Julieta Cuban Cigars given to Mr Percy Bower, Manager of the cigar department of his suppliers, the Army and Navy Stores to mark the end of the war, are displayed on January 13, 2012 in London, England. (Photo by Matthew Lloyd/Getty Images)

Female of pygmy hippopotamus called Malaya from Netherlands in zoo in Dvur Kralove nad Labem, Czech Republic, February 22, 2016. (Photo by David Tanecek/CTK via ZUMA Press)

A guard dog in the suburbs of Yakutsk, Russia, considered to be the coldest city in the world, January 2014. (Photo by Amos Chapple/REX Features)

With six-inch fangs and weighing in at 600lb, Saber and Janda are no ­ordinary house cats. Yet these huge Bengal tigers live in Janice Haley’s suburban garden and are treated like ordinary pets. They are fed by hand, get strokes and cuddles, and white male Saber goes to sleep sucking on her finger. Janice’s life changed 20 years ago when she spotted an advert for a tiger training course in her local paper – and two years later arrived home with her first cub. Then in 2002 she bought Janda, who is now 12. Photo: The pair are best of friends. (Photo by Ruaridh Connellan/Barcroft Media)