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)

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)

Dhofar Region, Oman. Much of Oman is desert, but the Arabian Sea coast in the Dhofar region represents a startling difference in climate. This coastal region catches the monsoon rains, or khareef, during the summer months. Drenching rains fall primarily on the mountainous ridge that separates the lush, fertile areas along the coast from the arid interior, recharging streams, waterfalls and springs that provide plentiful water supplies in the fertile lowlands for the remainder of the year. Image taken by Landsat 5 on April 2, 2005. (Photo by USGS/NASA)

In photographer David Eger's “Cloned Photos” project, he has recreated historical photographs, movie posters, and imagery using Clone Troopers and other Star Wars figures.

Photo: «Abbey Road». (Photo by David Eger)

Director Don Hahn attends “The Lion King 3D” Premiere during the 6th International Rome Film Festival on November 4, 2011 in Rome, Italy. (Photo by Getty Images/Getty Images)

The hull on a boat that carried Rohingya migrants for three months is seen at Langkawi island, in the Malaysia's northern state of Kedah, Malaysia, May 12, 2015. Thailand and Malaysia may set up camps and detention centers to shelter hundreds of refugees arriving on their shores, officials said on Tuesday, as a leading inter-governmental agency said about 7,000 boat people were still adrift in the Bay of Bengal. (Photo by Olivia Harris/Reuters)

Gaza authorities say two newborn lion cubs just unveiled by Hamas as prized additions in a zoo they run have died. Mohammad Abdel-Rahman, the acting manager of the Beit Lahiya zoo in northern Gaza, said Thursday the cubs died of an unspecified illness. He said the zoo's staff was unable to save them because they lacked experience in caring for newborn cubs. Photo: Two-day-old lion cubs Fajr and Sjel are fed at a zoo in the northern Gaza Strip town of Beit Lahia, on November 19, 2013. (Photo by Mohammed Abed/AFP Photo)