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)

Martin De Pasquale with his creative photographs. Here's a look at the incredible world of a digital artist who creates mind-bending works of art with Photoshop. (Photo by Martin De Pasquale/Caters News)

These images by Buenos Aires-based graphic design student Martín De Pasquale are so surreal that, obviously, you know they are photoshopped. But they are perfectly executed and very funny. To learn more about the artist and the art of photoshopping we suggest you to check out some of his behind the scenes photos in his Fotografía Imposible folder on Facebook.

Women wearing traditional costumes chat during the first day of the April Fair celebrations in Sevilla, southern Spain, 15 April 2018. The April Fair, running from 15 April until 21 April, is a traditional celebration in Sevilla, attracting thousands of visitors each year. (Photo by Raúl Caro Cadenas/EPA/EFE)

A relic hunter dubbed “Indiana Bones” has lifted the lid on a macabre collection of 400-year-old jewel-encrusted skeletons unearthed in churches across Europe. Art historian Paul Koudounaris has hunted down and photographed dozens of gruesome skeletons in some of the world's most secretive religious establishments. Photo: Albertus in the church of St George in Burgrain, Germany. Incredibly, some of the skeletons, which took up to five years to decorate, were even found hidden away in lock-ups and containers. (Photo by Paul Koudounaris/BNPS)

French artist Olivier Grossetête used three enormous helium balloons to float a rope bridge over a lake in Tatton Park, a historic estate in north-west England.