On Dale A. Browne’s first trip to Yellowstone, he “got the best shot” he’d ever taken after chasing this weasel for 30 minutes. The trip for the 58-year-old from Manassas, Va., was a gift from his wife and an opportunity to improve his photography skills with the help of guide and professional photographer Tom Murphy. (Murphy did not assist in the taking of this photo). (Photo by Dale A. Browne)

Commended. In late May, about a quarter of a million snow geese arrive from North America to nest on Wrangel Island, in northeastern Russia. They form the world's largest breeding colony of snow geese. Photographer Sergey Gorshkov spent two months on the remote island photographing the unfolding dramas. Arctic foxes take advantage of the abundance of eggs, caching surplus eggs for leaner times. But a goose (here the gander) is easily a match for a fox, which must rely on speed and guile to steal eggs. “The battles were fairly equal”, notes Sergey, “and I only saw a fox succeed in grabbing an egg on a couple of occasions, despite many attempts”. Surprisingly, “the geese lacked any sense of community spirit”, he adds, “and never reacted when a fox harassed a neighboring pair nesting close by”. (Photo by Sergey Gorshkov/Veolia Environnement Wildlife Photographer)

Ngorongoro Crater (Tanzania). At 610m deep and 260 sq km, this is the largest unflooded caldera in the world. A blue-green vision from above it's a haven for engangered wildlife and Maasai livestock. The crater was formed three million years ago when a giant volcano, which could have been as high as Kilimanjaro, exploded and collapsed. The caldera formed the concentric fractures in the crust cracked down to a magma reservoir deep underground. (Photo by John Bryant/Getty Images)

Runners wearing full solid-coloured bodysuits take part in a marathon in Tel Aviv, Israel February 26, 2016. Tens of thousands took part in the event, which saw streets closed off from Rokach Boulevard in the north to Jaffa’s Jerusalem Boulevard in the south. Other than the main 42-kilometer (26-mile) run, the day’s events also included a half-marathon route, several shorter circuits, a handcycle race for the handicapped and a mini-marathon for kids of a single kilometer (0.6 miles). (Photo by Amir Cohen/Reuters)

In this January 12, 2015 photo, a wall of collectable sneakers are displayed at Sneaker Pawn in the Harlem section of New York. Basketball sneakers can re-sell for hundreds of dollars, depending on the model, the size of the production run and how easy it is to find a pair in good condition. (Photo by Seth Wenig/AP Photo)

In this Sunday, September 18, 2016 photo, participants wait on stage ahead of Miss Trans Star International 2016 show celebrated in Barcelona, Spain. (Photo by Emilio Morenatti/AP Photo)

A bride stretches before the event during the “Running of the Brides” race, in Bangkok, Thailand, December 2, 2017. Six hundred of to be brides and their grooms compete a run race aimed to win more than two million baht (61,000 US dollars or 51,000 euro) of wedding package prizes including a pair of white gold diamond rings and honeymoon trip to the Maldives. (Photo by Athit Perawongmetha/Reuters)

Full length portrait of female skier, Sierra Nevada Mountains in California, USA. (Photo by Anatoliy Gleb/Getty Images)