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)

The fourth annual BigPicture Natural World Photography Competition aims to celebrate the diversity of life on Earth, and encourages people to protect and conserve it. Here: “The Salmon Catchers”. Terrestrial Wildlife. To capture this view of a mother grizzly bear and her cub, photographer Peter Mather set up a camera trap on a log that he knew the bears tended to traverse while fishing for salmon, in the Yukon River watershed in Canada. (Photo by Peter Mather/BigPicture Natural World Photography Competition 2017)

The players of Denmark huddle prior to the FIFA Women's World Cup qualifier match between Denmark and Sweden at Viborg Stadion on September 4, 2018 in Viborg, Denmark. (Photo by Lars Ronbog/FrontZoneSport via Getty Images)

A reveller takes part with her dogs in the annual halloween dog parade at Manhattan’s Tompkins Square Park in New York, U.S. October 22, 2016. (Photo by Eduardo Munoz/Reuters)

Daniela Burza, 45, wears a Nasty Woman t-shirt and a mask of U.S. Democratic presidential nominee Hillary Clinton as she competes during the Haunted Heats Halloween Surf Contest in Santa Monica, California, U.S., October 29, 2016. (Photo by Lucy Nicholson/Reuters)

A woman dressed up for Halloween travels on a Metro train in São Paulo, Brazil on October 30, 2017. (Photo by Cris Faga/Rex Features/Shutterstock)

Model Heide Lindgren attends Heidi Klum's 12th annual Halloween party at the PH-D Rooftop Lounge at Dream Downtown on October 31, 2011 in New York City. (Photo by Jemal Countess/Getty Images)