Workers attempt to bring a tranquillised black rhino to the ground before dehorning in an effort to deter the poaching of one of the world's endangered species, at a farm outside Klerksdorp, in the north west province, South Africa, February 24, 2016. (Photo by Siphiwe Sibeko/Reuters)

New York City policemen tangled with demonstrators at a subway station on the opening day of the New York World's Fair, April 22, 1964. Youths attempted to stall the train, which was headed from the city to the fairgrounds, as a form of protest on behalf of civil rights for blacks. (Photo by Charles Gorry/AP Photo)

A General Atomics MQ-9 Reaper stands on the runway during “Black Dart”, a live-fly, live fire demonstration of 55 unmanned aerial vehicles, or drones, at Naval Base Ventura County Sea Range, Point Mugu, near Oxnard, California July 31, 2015. (Photo by Patrick T. Fallon/Reuters)

Revellers take part in the “Canto a la Tierra” parade on January 3, 2018, during the Carnival of Blacks and Whites in Pasto, Colombia, the largest festivity in the south- western region of the country. More than 10,000 people among artists, craftsmen and revellers take part in the Blacks and Whites Carnival, which has its origins in the mix of the multiple Andean, Amazonian and Pacific cultural expressions. It is celebrated every year from January 2 to 6 in the city of Pasto and is part of UNESCO's Intangible Cultural Heritage of Humanity since 2009. (Photo by Luis Robayo/AFP Photo)

Find out what 2014 has in store for you and your cash. Provided by Russell Grant Horoscopes. (Photo by Toma Petrovic)

Judy, a black collie whose owner was killed by a train when trying to retrieve her after she slipped her lead. (Photo by Evening Standard/Getty Images). 17th December 1976

Vladimir Putin shows a hold to a young judo wrestler at the Regional Judo Center at the Arena Sports Complex in the Siberian city of Kemerovo on January 24, 2012, during his visit to the region. Putin is known for his passion for judo, in which he has a black belt. (Photo by AFP Photo/STR)

A cloud of black smoke billows out the exhaust pipe of John Robertson's diesel dragster as he runs down the track during the 2015 NHRA Kansas Nationals, Friday, May 22, 2015, at Heartland Park in Topeka, Kan. (Photo by Chris Neal/The Topeka Capital-Journal via AP Photo)