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)

An anti-lockdown activist dressed as Father Christmas is arrested in Grosvenor Square during a demonstration in London, England, on November 28, 2020. London is to return to “Tier 2” or “high alert” covid-19 restrictions once the current England-wide coronavirus lockdown ends next Wednesday. All three of the tiers, assigned to local authorities across England, have been strengthened since the lockdown began on November 5, however, with the main impacts to be felt by the hospitality sector. (Photo by Mark Thomas/i-Images)

Faith Lynch (L) and Molly Beck (R) pose for a photo at Hackney Bridge as fans gather to watch a live broadcast of the semi-final match between England and Denmark on July 07, 2021 in London, England. England has reached the semi-finals of the UEFA European Football Championship 2020 hoping to make the final for the first time in the history of the competition. (Photo by Leon Neal/Getty Images)

Team Canada's Kyra Constantine, left, and Team England's Jessie Knight cross the finish line of the Women's 4 x 400 meters relay during the athletics competition in the Alexander Stadium at the Commonwealth Games in Birmingham, England, Sunday, August 7, 2022. England crossed ahead but was later disqualified and Canada took the gold medal. (Photo by Manish Swarup/AP Photo)

A Tyrannosaurus Rex dinosaur costume runs on the field as young boys play an exhibition soccer match during halftime of the MLS soccer game between the Los Angeles Galaxy and Seattle Sounders FC in Carson, California May 26, 2013. The dinosaur was on the field to promote the Natural History Museum of Los Angeles County. (Photo by Danny Moloshok/Reuters)

Women carry gas cylinders to fill them at a distribution point in Cairo January 19, 2015. Egypt is going through its worst energy crisis in decades and is seeking fresh sources of natural gas, which powers most of its homes and factories. (Photo by Mohamed Abd El Ghany/Reuters)