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)

Two of the first six “neighborhood electric vehicles” (NEV) to be leased by the U.S. Army are on display during an introductory ceremony at Fort Myer January 12, 2009 in Arlington, Virginia. The Army has leased 800 of the non-tactical NEVs with a goal of 4,000 vehicles by 2011. These NEVs are manufactured by the Global Electric Motorcars division of Chrysler Corporation. With a full eight-hour charge, the NEVs can traverse 30 miles at a top speed of 25-miles-per-hour. (Photo by Chip Somodevilla/Getty Images)

Photographer Brian Finke spent nearly two years traversing the friendly skies, following the life of flight attendants in the air and on the ground, from Delta and Hawaiian Air, to Hooters Air, Southwest, Air France, British Airways, Air Asia, and dozens more. His images of flight attendants waving, applying makeup and deboarding plans while smiling appear as if they were ripped from an advertisement in a glossy magazine. Here: Tiger Airways, Singapore, 2006. (Photo by Brian Finke/The Washington Post)

Floating on clear deep water and reflections near the cave entrance. Visitors can either bring their own kayaks or rent boats from the local community to paddle deep inside the cave and marvel at its wonders on March 2015 at Tham Khoun Ex, Laos. Tham Khoun Xe, commonly known as the Xe Bang Fai River Cave, in Laos, has over 15km of passages filled with awe-inspiring views and wide expanses of water. Photographer, John Spies, 59, captured scenes from the entrances of the huge underground river passages, intricate cave formations and views from a passage high above the water. The cave is formed by the Xe Bang Fai river, a major tributary of the Mekong and in the dry season can be traversed using inflatable kayaks. (Photo by John Spies/Barcroft Media/ABACAPress)

Male is the capital and most populous city in the Republic of Maldives. The city is geographically located at the southern edge of North Malé Atoll (Kaafu Atoll). Administratively, it is a city-class constituency and is governed by the Malé City Council. Traditionally it was the King's Island, from where the ancient Maldive Royal dynasties ruled and where the palace was located. The city was then called “Mahal”. Formerly it was a walled city surrounded by fortifications and gates (doroshi).

In this handout image provided by the City of New York, a Nissan NV200 is seen as a New York City taxi cab in New York City. The Taxi and Limousine Commission along with New York City Mayor Michael Bloomberg announced the Nissan NV200 designed by Nissan North America, Inc., has been chosen as the winner of the Taxi of Tomorrow competition and will become the City's exclusive taxicab for a decade. (Photo by City of New York via Getty Images)

A Manchester City fan attends the trophy ceremony after the end of the Soccer Club World Cup final match between Manchester City FC and Fluminense FC at King Abdullah Sports City Stadium in Jeddah, Saudi Arabia, Friday, December 22, 2023. Manchester City won 4-0. (Photo by Manu Fernandez/AP Photo)