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)

This combination of April 15, 2013 and April 2, 2014 photos show a police officer clearing Boylston Street following a bomb blast near the finish line of the 2013 Boston Marathon, and pedestrians crossing at the same corner nearly a year later in Boston. (Photo by Charles Krupa/AP Photo)

From Britain to China to Mali, new maps showing travel times to the nearest urban centre reveal huge differences between countries. Using Open Street Map and Google, a University of Oxford team have created a visual breakdown that suggests major inequalities when it comes to commuting. Here: China. The dataset used for China was unique as it relied solely on Open Street Map, due to restrictions on accessing Google data. The population is densely concentrated in the east and accessibility is increased, whereas rural provinces in the west remain remote. (Photo by Daniel Weiss/Jennifer Rozier/Malaria Atlas Project/University of Oxford)

People gather to view a new art installaiton at Waterfront Park entitled, Interstellar Influencer (Make an Impact) by Jason Klimoski and Lesley Chang of STUDIOKCA on Saturday March 30, 2024 in Alexandria, VA. The artwork depicts an asteroid that struck the region millions of years ago. (Photo by Matt McClain/The Washington Post)

A member of the Grupa Magnifica acrobatics club poses for a photo on the Baltic Sea beach during sunset in the town of Leba, Pomeranian region, on August 6, 2024. (Photo by Sergei Gapon/AFP Photo)

An observer watches the Perseid meteor shower at Mount Hamilton in California, United States on August 13, 2023. (Photo by Tayfun Coskun/Anadolu Agency via Getty Images)

A woman has her hair blown by the wind during a snowstorm in Quebec City, on December 22, 2013. (Photo by Mathieu Belanger/Reuters)

Hindu women apply “sindhur”, or vermillion powder, on the face of a woman after worshipping the idol of the Hindu goddess Durga on the last day of the Durga Puja festival in Chandigarh, India October 11, 2016. (Photo by Ajay Verma/Reuters)