A female Kurdistan Workers Party (PKK) fighter stands near a security position in Sinjar, March 13, 2015. Women fighters at a Kurdistan Workers Party (PKK) base on Mount Sinjar in northwest Iraq, just like their male counterparts, have to be ready for action at any time. Smoke from the front line, marking their battle against Islamic State, which launched an assault on northern Iraq last summer, is visible from the base. Many of the women have cut links with their families back home; the fighters come from all corners of the Kurdish region. (Photo by Asmaa Waguih /Reuters)

A performer wearing costumes walk on stilts before a show during a lantern fair at the beginning of Chinese Lunar New Year, in Xi'an, Shaanxi province, February 11, 2016. (Photo by Reuters/Stringer)

Two biplanes of the Team Breitling cross during a training flight prior the AIR14 air show in Payerne, Switzerland, August 29, 2014. (Photo by Peter Schneider/EPA)

Andrej Ciesielski dangels his legs off the side of a building overlooking Times Square, New York City. (Photo by Andrej Ciesielski/Caters News Agency)

“Winter Climbing from inside Ben Nevis”. The view from inside the mountain, as a winter climber passes through the cave on Minus Three gully. Photo location: Ben Nevis, Fort William, Scotland. (Photo and caption by Daniel Wildey/National Geographic Photo Contest)

The proliferation of marijuana edibles for both medical and recreational purposes is giving rise to a cottage industry of baked goods, candies, infused oils, cookbooks and classes that promises a slow burn as more states legalize the practice and awareness spreads about the best ways to deliver the drug. Edibles and infused products such as snack bars, olive oils and tinctures popular with medical marijuana users have flourished into a gourmet market of chocolate truffles, whoopie pies and hard candies as Colorado and Washington legalized the recreational use of marijuana in the past year. Photo: In this Thursday, July 10, 2014, photo, Mike Fitzgerald, right, teaches behind a sample display of cannabis-infused products during a cooking class at the New England Grass Roots Institute in Quincy, Mass. (Photo by Michael Dwyer/AP Photo)

The Wildscreen festival is the world’s biggest celebration of screen-based natural history storytelling which takes place every two years in Bristol. Here: “Walrus in Midnight Sun”. Walrus feed mostly on bivalves in productive, shallow and often sandy habitats in the Arctic. This individual, though, arrived on a beach outside Tromsø, northern Norway, and found comfort on a stranded dead sperm whale. After two weeks he approached Audun, and only half a metre away he stretched his tusk forward and touched his hand gently. “This was one of the most memorable moments of my life”, Rikardsen says. He named the 500kg male Buddy. After two months, the dead whale was decomposed and Buddy suddenly disappeared. (Photo by Audun Rikardsen/Wildscreen 2016)