In this February 19, 2017 photo, a couple dances during the “If you don't give me....then you lend me” Carnival street party on Ipanema beach, in Rio de Janeiro, Brazil. The typical view of Carnival in Brazil is anything goes, with no headdress too big, no outfit too small, no song too ribald, but this year some organizers of the world's best known party are drawing the line at lyrics that are sexist, homophobic or racist. (Photo by Silvia Izquierdo/AP Photo)

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)

Bathing suit models are shown listening to the radio on the beach, circa 1940's. (Photo by Bettmann Archive/Getty Images)

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)

A relative (L) of Champa Devi, 88, sits next to her body, minutes after her death at Mukti Bhavan (Salvation House) at Varanasi, in the northern Indian state of Uttar Pradesh, June 21, 2014. The city of Varanasi, on the banks of the River Ganges, is widely considered Hinduism's holiest city and many Hindus believe that dying there and having their remains scattered in the Ganges allows their soul to escape a cycle of death and rebirth, attaining “moksha” or salvation. “Mukti Bhavan” or “Salvation House”, is a charity-run hostel that caters for people who wish to come to Varanasi to die. Guests can normally stay up to two weeks after which, if they haven't yet passed away, they are gently asked to leave. (Photo by Danish Siddiqui/Reuters)

People protest at the Boston Free Speech Rally in Boston, USA on August 19. 2017. With the Boston Free Speech rally was closed to the media (despite the Boston Common being a public space), a lot of the media’s coverage centred on the tensions within the larger counter-protest. (Photo by Stephanie Keith/Reuters)

Elephants munch on Christmas trees in their enclosure at Berlin's Zoologischer Garten Zoo on January 4, 2013 in Berlin, Germany. Traditionally, the animals get in the first week of the year leftover Christmas trees. (Photo by Andreas Rentz)

Children in Hiroshima, Japan, wearing masks to combat the odour of death after the city was destroyed by the first atom bomb. (Photo by Keystone/Getty Images). 1945