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)

Ukrainian service man Oleksandr of 24th brigade stands guard at his position in the trenches at the frontline, amid Russia?s attack on Ukraine near Niu York, Donetsk region, Ukraine on April 4, 2023. (Photo by Kai Pfaffenbach/Reuters)

Bosnian men urge their horses to pull logs up a hill during a competition in the Bosnian town of Sokolac 50 kms west of Sarajevo, Bosnia,on Monday, April, 13, 2015. The annual festival celebrates the centuries old tradition of pulling logs honoring the owners of the strongest horses. Owners of the horses gather from all over Bosnia and beyond, and compete in a show of horse strength. (Photo by Amel Emric/AP Photo)

A man wades through a water-logged road after rains ahead of Cyclone Yaas at Digha in Purba Medinipur district in the eastern state of West Bengal, India, May 26, 2021. (Photo by Rupak De Chowdhuri/Reuters)

“A snapshot from mountaineer's life”. Have you ever wondered how does a mountaineer's day start? I will give you a hint: you wake up at 3 am, set the stove, wake up your partner, pretend it is warm, quickly consume a high-calorie breakfast, watch your friends slowly ascending the icy slopes of your dream summit with their tiny head torches glimmering against perfectly blue ice, and hope for the good weather. One would ask: why all this trouble? The answer is easy: for the love of the adventure and the unknown. Location: Chamonix, Haute Savoye, France. (Photo and caption by Kamil Tamiola/National Geographic Traveler Photo Contest)

ATTENTION! All pictures are presented in high resolution. To see Hi-Res images – just TWICE click on any picture. In other words, click small picture – opens the BIG picture. Click BIG picture – opens VERY BIG picture.

Ukrainian serviceman Valerii looks on at a position in a frontline, amid Russia's attack on Ukraine, in Mykolaiv region, Ukraine on October 26, 2022. (Photo by Valentyn Ogirenko/Reuters)

A mural is seen on a heavily damaged residential building in the frontline town of Avdiivka, Donetsk region on April 25, 2023, amid the Russian invasion of Ukraine. (Photo by Anatolii Stepanov/AFP Photo)

A Ukrainian serviceman of the 53rd brigade fires a RPG-9 towards Russian positions at the frontline close to Donetsk, Ukraine, Saturday, August 19, 2023. (Photo by Libkos/AP Photo)