A knife is seen beside a bowl containing blood after a ram was killed as a sacrifice in front of a shrine at the annual voodoo festival in Ouidah, Benin, January 10, 2016. In Ouidah, a small town and former slave port in the West African country of Benin, the annual voodoo festival gathers visitors from far and wide. It's a week that brings together priests and dignitaries, rich and poor, locals and visitors from as far afield as the Caribbean and France. The festival commemorates the estimated 60 million people who lost their homelands and their freedom during the African slave trade. (Photo by Akintunde Akinleye/Reuters)

A man carrying an axe walks past a house marked with bullet holes in Gyallesu district after recent clashes between Shi'ites and the army in Zaria, Kaduna state, Nigeria, February 3, 2016. Sectarian tensions are rising in Nigeria's Muslim north, where hundreds of Shi'ites were killed in clashes with the army in the town of Zaria in December, according to Shi'ites and rights groups. Following the clashes, bulldozers sent by the state levelled Shi'ite shrines, a cemetery and offices in the deeply divided town. The region is already grappling with an insurgency waged by the jihadist Boko Haram group. (Photo by Afolabi Sotunde/Reuters)

A girl paddles on her stand-up board on the waters of Guanabara bay at Bica beach in Rio de Janeiro Brazil, January 10, 2016. Few features capture the beauty, or the problems, of one of the world's most dramatic urban landscapes like Guanabara Bay - the finger-like inlet that forms the shoreline and harbor for Rio de Janeiro. The bay, which carves into southeast Brazil from the Atlantic Ocean, literally gave Rio its name when Portuguese mariners mistook it for a “rio”, or “river”. Four centuries later, the bay is preparing to welcome another sort of seafarer – Olympic sailors, who will navigate the bay when the 2016 Rio Olympics kick off in August. (Photo by Ricardo Moraes/Reuters)

The anthropometric record card of Sarah Giles, a servant who was convicted of stealing in 1897, on display making up part of a mosaic of cards on a table top during a press preview for the Crime Museum Uncovered exhibition at the Museum of London in the City of London, Wednesday, October 7, 2015. Drawn from Scotland Yard's private collection, the show charts more than a century of violence and suffering, from the murders of Jack the Ripper to IRA and al-Qaida bombings. But it also celebrates the brains, bravery and scientific advances that helped catch perpetrators and solve crimes. (Photo by Alastair Grant/AP Photo)

An area of vegetation can be seen amongst drought effected farmland in South Australia, November 12, 2015. A pioneering Australian scheme to improve the management of water in the world's driest inhabited continent is facing its first real test as an intensifying El Nino threatens crops and builds tensions between farmers and environmentalists. An El Nino, a warming of sea-surface temperatures in the Pacific, is already causing drought and other extreme weather, affecting millions of people across parts of the world, and experts warn that the intensifying weather pattern could emerge as one of the strongest on record. (Photo by David Gray/Reuters)

The British Breitling Wingwalkers, Danielle Hughes and Emily Guilding, soar above the Palm Jumeirah in Dubai at 1,500 feet (460 meters) in excess of 100mp/h, ahead of their Dubai debut performance at the 2014 UIM Skydive Dubai XCAT World Powerboating Series, on Saturday, 13th December 2014. The British team is the only aerobatic formation display team who employ full time wingwalkers and fly their two Breitling-liveried 1930's Boeing Stearman bi-planes at Air Shows and major sporting events around the world. (Photo by Katsuhiko Tokunaga/Breitling via AP Images)

A volunteer pets a tiger inside a cage at the Wat Pa Luang Ta Bua, otherwise known as Tiger Temple, in Kanchanaburi province February 12, 2015. Thai officials last week raided the Buddhist temple that is home to more than 100 tigers and are currently conducting an investigation into suspected links to wildlife trafficking. Authorities from Thailand's Department of National Parks, Wildlife and Plant Conservation on Thursday checked 143 Bengal tigers living at the temple, and found them to be in good health. (Photo by Athit Perawongmetha/Reuters)

In this Thursday, January 17, 2019, photo, an Indian tamer reacts as a bull charges towards him during a traditional bull-taming festival called Jallikattu, in the village of Allanganallur, near Madurai, Tamil Nadu state, India. Jallikattu involves releasing a bull into a crowd of people who are expected to hang on to the animal's hump for a stipulated distance or hold on to the hump for a minimum of three jumps made by the bull. The sport, performed during the four-day “Pongal” or winter harvest festival, is hugely popular in Tamil Nadu. (Photo by Aijaz Rahi/AP Photo)