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 “Assignments” exhibition is an annual chance to see the top images by UK photojournalists, as chosen by the British Press Photographers’ Association. Here: Wales’s Cory McKenna dominates Micol DiSegni during their fight at Cage Warriors 97 in Cardiff, 29 September 2018. (Photo by Chris Fairweather/Huw Evans Agency)

Sophie Turner (L) attends HBO's Official 2019 Emmy After Party on September 22, 2019 in Los Angeles, California. (Photo by Jeff Kravitz/FilmMagic for HBO)

Yuchen Chao of Chinese Taipei in action during the Beach Handball Women's Tournament match between Chinese Taipei and Paraguay at The Beach Handball Arena, Tecnopolis Park, Buenos Aires, Argentina, October 12, 2018. (Photo by Lukas Schulze for OIS/IOC/Handout via Reuters)

Smoke plumes rise from Mount Etna, one of the most active volcanoes in the world in Sicily, Italy on June 28, 2016. (Photo by Etna Walk/Rex Feature/Shutterstock)

Fishermen pull up a live 2.5 metre crocodile in their net in the Western Amazon region, Brazil on September 20, 2017. The fishermen were fishing for a large river fish called Arapaima but sometimes crocodiles become stuck in the nets as well. (Photo by Carl de Souza/AFP Photo)

An Indian journalist poses with the wax statue of American actress Kim Kardashian (L) and American actor Will Smith (R) during the launch of Madame Tussauds Delhi in New Delhi on November 30, 2017. The wax museum will be open for the visitors from 01 December on. Madame Tussauds New Delhi features 50 wax figures of personalities from the fields of sports, music, film, history and politics. (Photo by Sajjad Hussain/AFP Photo)

A Southwest Airlines jet takes off from Reagan National Airport with a thunderhead to the east on June 20, 2017 in Alexandria, VA. (Photo by Jonathan Newton/The Washington Post)