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 wolfhounds take part in a dogfight in a stadium in the Kyrgyzstan capital Bishkek on November 5, 2017, during fights organized by a local breeders aiming to improve the Asian Shepherd breed, organizers said. (Photo by Vyacheslav Oseledko/AFP Photo)

North Koreans who signed up to join the army train in the midst of political tension with South Korea, in this undated photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang August 23, 2015. Top aides to the leaders of North and South Korea resumed talks on Sunday after negotiating through the night in a bid to ease tensions involving an exchange of artillery fire that brought the peninsula to the brink of armed conflict. (Photo by Reuters/KCNA)

An officer from the California Department of Fish and Wildlife gets ready to tranquillize a bear in Pasadena, California, U.S., August 20, 2021. (Photo by Mario Anzuoni/Reuters)

(L-R) American singers Gwen Stefani of No Doubt and Olivia Rodrigo perform at the Coachella Stage during the 2024 Coachella Valley Music and Arts Festival at Empire Polo Club on April 13, 2024 in Indio, California. (Photo by John Shearer/Getty Images for No Doubt)

In a January 19, 2014 photo Phillip Seymour Hoffman poses for a portrait at The Collective and Gibson Lounge Powered by CEG, during the Sundance Film Festival in Park City, Utah. Hoffman, who won the Oscar for best actor in 2006 for his portrayal of writer Truman Capote in “Capote” was found dead Sunday in his apartment in New York with what law enforcement officials said was a syringe in his arm. He was 46. (Photo by Victoria Will/AP Photo/Invision)

“One in Eight Hundred” by Mario Wezel, from Germany, is the winner of the “People” category. The title refers to the odds given to Martin and Karina at their prenatal screening before their daughter, Emmy, was born. The five-year-old from Denmark has Down's Syndrome. (Photo by Mario Wezel/Sony World Photography Awards)

A lizard wears a cowboy hat at Pet Expo Thailand on May 06, 2023 in Bangkok, Thailand. Dogs take part in a skateboarding competition at Pet Expo Thailand, a four day exhibition held at the Queen Sirikit National Convention Center. Dogs were judged on form and agility and separated into novice and experienced categories. Placing first place in the novice category was Mui and first in the experienced category was Suradej. Both house pets and exotic animals were featured at the expo, with visitors and their pets able to interact with them. (Photo by Lauren DeCicca/Getty Images)