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)

Wakodahatchee wetlands, Delray Beach, Florida, US. Equipped with sinewy necks and spear-like bills, great blue herons can lunge with fearsome speed to strike their aquatic prey. Adults will also employ rapid stabbing motions as one aspect of their complex courtship displays; they’re seemingly dangerous moves, but fitting to the intensity of mating season. (Photo by Melissa Rowell/Audubon Photography Awards)

This image provided by NASA shows parts of Europe and Africa very easily recognizable in this night time image shot by one of the Expedition 25 crew members aboard the International Space Station flying 220 miles above Earth on Thursday October 28, 2010. The view “looks” northward over Sicily and the “boot” of Italy, with the Mediterranean Sea representing most of the visible water in the view and the Adriatic Sea to the right of center. Tunisia is partially visible at left. Part of a docked Russian spacecraft and other components of the ISS are in the foreground. (Photo by AP Photo/NASA)

A student works on her skills during an acrobatics class near the pier in Huntington Beach, CA on Monday, August 17, 2020. Instructors at the Orange County Performing Arts Academy decided to bring the class to the beach from Anaheim Hills to beat the heat and give the students an end of the summer treat. (Photo by Paul Bersebach/The Orange County Register via AP Photo)

Eryn, owned by Tom Chudleigh in Canada. New global research has revealed that ‘shed-scapism’ is sweeping the world with more people than ever ditching their tools and transforming their sheds into zen dens. The research comes as the Cuprinol Shed of the Year competition joins forces with aspirational shed fan site, Cabin p*rn, to launch the first ever global category. We have a stunning suite of imagery of 9 sheds from across the world - from Norway to Slovenia, British Colombia to Colorado who have all submitted their sheds in the hopes of being crowned the first ever Global Shed of the Year. (Photo by Cuprinol/Rex Features/Shutterstock)

Photographer Ma Hongjie has spent 11 years documenting families in various parts of China for his upcoming book The Family Belongings of Chinese People. Here: a couple with their belongings and vegetables in Hebei Huailai county. (Photo by Ma Hongjie)

This Monday, September 15, 2014 photo shows glazed bricks displayed at the Iraqi National Museum in Baghdad. The Islamic State militants seek to purge society of all influences that don't conform with their strict, puritanical version of Islam. That means destroying not only relics seen as pagan but also Muslim sites they see as contradicting their ideology, particularly Sunni Muslim shrines they see as idolatrous as well as mosques used by Shiites, a branch of Islam they consider heretical. (Photo by Hadi Mizban/AP Photo)

A hooded protester throws a petrol bomb to riot policemen during clashes, following a rally marking the 43rd anniversary of a 1973 student uprising against the military dictatorship that was ruling Greece, in Athens, Greece, November 17, 2016. (Photo by Yannis Behrakis/Reuters)