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)

Children play in their grandmother's garden in a suburb of Budapest, Hungary, Thursday, July 21, 2022. Hungary has experienced several heat waves since mid June with day-time temperatures rising to 40 degrees Celsius and remaining at tropical levels through the night. In fact, the country recently shattered record for its hottest night ever when temperature of 25.4 C was measured in Budapest on July 26. (Photo by Anna Szilagyi/AP Photo)

Children play in water to beat the heat during the Muslim holy month of Ramadan amid lockdown of the Sindh province due to the ongoing coronavirus COVID-19 disease pandemic in Karachi, Pakistan, 28 April 2020. Muslims around the world celebrate the holy month of Ramadan, by praying during the night time and abstaining from eating, drinking, and sexual acts during the period between sunrise and sunset. Ramadan is the ninth month in the Islamic calendar and it is believed that the revelation of the first verse in Koran was during its last 10 nights. (Photo by Shahzaib Akber/EPA/EFE)

Mohammed Al-Dahshan, who decorates himself and his horse with led lights, performs the Ramadan drumming on the north of the Egyptian capital Cairo on March 20, 2025. Al-Dahshan and his horse hit the road at sahur (Ramadan meal eaten at night) time, wandering the streets of Dekernes region every night during Ramadan and waking people up for sahur. (Photo by Mohamed Elshahed/Anadolu via Getty Images)

Backdropped by a night time view of the Earth and the starry sky, the Space Shuttle Endeavour is seen docked to the International Space Station on May 28, 2011. (Photo by Reuters/NASA)

Love Island babe Jessica Hayes has wild night out with Ryan Mira at Bubbles Beach Club and SoHo nightclub in Liverpool, England on September 8, 2016. (Photo by Danny Ryan/iCelebTV)

A church made entirely from ice is seen during the night at Balea Lac resort in the Fagaras mountains January 29, 2015. (Photo by Radu Sigheti/Reuters)

People take part in a traditional mid-summer solstice night celebration (Rasos Festival) at the Open-Air Museum of Lithuania in Rumsiskes, east of Kaunas, Lithuania, on late June 23, 2020. (Photo by Petras Malukas/AFP Photo)