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)

“Catch of the Decade”. Can you guess what happened next? Photo location: Katmai National Park, Alaska, USA. (Photo and caption by Aaron Baggenstos/National Geographic Photo Contest)

Second placed Kalex Moto2 Tito Rabat (rear R) of Spain and third placed Kalex Moto2 Alex Rins of Spain spray with champagne during the award ceremony for the Czech Grand Prix in Brno, Czech Republic, August 16, 2015. (Photo by David W. Cerny/Reuters)

Chinese women run with a ball on a snow covered field in Shenyang in China's northeastern Liaoning province during International Women's Day on March 8, 2018. International Women's Day is celebrated on March 8 every year and commemorates the movement for women's rights. (Photo by AFP Photo/Stringer)

American model and television personality Kendall Jenner attends the Tiffany & Co. Paper Flowers event and Believe In Dreams campaign launch on May 3, 2018 in New York City. (Photo by Jamie McCarthy/Getty Images for Tiffany & Co.)

English singer Rita Ora, 29, made sure all eyes were on her as she headed for a night out in a plunging dress in London, England on September 7, 2020. The sеxy checked dress was complemented with heavy gold jewellery around Rita's wrists and neck. Rita's blonde hair had a sheen as it fell over her shoulders, and she completed her look with glam makeup. (Photo by Instagram/The Sun)

A female black lemur (Eulemur macaco), looks at a camera in its enclosure at Bioparc Fuengirola in Fuengirola, near Malaga, southern Spain, February 8, 2017. (Photo by Jon Nazca/Reuters)

One month-old endangered Bornean Orang Utan sleeps on his mother named Miri on Wednesday, March 6, 2013, in Singapore. The Singapore Zoo is renowned for its flagship animal, the Orang Utan, and exhibits both the endangered Bornean and critically endangered Sumatran sub-species in a social setting. It is also known for its efforts in promoting and educating the public about the importance of wildlife conservation through its educational programs and breeding of these endangered species. (Photo by Wong Maye-E/AP Photo)