Participants wearing superhero costumes attend the World DC Comics Super Heroes event in San Martin de Valdeiglesias, near Madrid, April 18, 2015. To celebrate the anniversary of the publication of the very first Superman story, DC Comics are asking fans to help set a new world record for the largest global gathering of people dressed as DC Comics Super Heroes. (Photo by Andrea Comas/Reuters)

A pair of ice climbers have been snapped in front of a stunning aurora. Mike Stuart and Takeshi Tani were climbing the Athabasca Glacier in Alberta, Canada, when the aurora lit up the nights sky. They were photographed by famed night-time photographer Paul Zizka, who specialises in photographing auroras in some of Canadas most beautiful parks. (Photo by Paul Zizka/Caters News)

NYC no pants subway ride. Thousands of straphangers took their pants off for the 15th annual "No Pants Subway Ride" hosted by Improv Everywhere. People gathered at seven meeting points throughout the five boroughs at 3PM. All participants met up at Union Square around 5PM to and had a pant-less celebration and the afterparty at Webster Hall. (Photo by Paul Martinka/The New York Post)

Dead sperm whales are seen washed up on a beach on Texel Island, The Netherlands, January 13, 2016. The five sperm whales that beached on the Dutch lsland of Texel on Tuesday have died overnight, Dutch media reported. It is extremely unusual for so many whales to be in Dutch waters, a spokesman for the Ecomare marine centre told local paper Noordhollands Dagblad. Efforts to get the whales back into open water on Tuesday evening failed and rescuers finally withdrew from the beach at around midnight. The area of beach where the whales are has been closed to the public, to minimise the distress to the animals. (Photo by Cris Toala Olivares/Reuters)

A general view shows the Krasnoyarsk hydro-electric power station on the Yenisei River near the Siberian city of Krasnoyarsk, Russia, January 13, 2016. The power plant, owned by EuroSibEnergo company, part of En+ Group, with a generating capacity of 6,000 megawatt (MW), has a ferro-concrete dam 124-metres high and 1065-metres long and is the second largest Russian hydroelectric power station. About 85% of the energy generated is intended for the Rusal Krasnoyarsk aluminium smelter, according to representatives of the power station. (Photo by Ilya Naymushin/Reuters)

Up to 35% of Mongolians still live a nomadic life, depending on their land to survive. But environmental changes, particularly desertification, means this way of life is under threat. Korean photographer Daesung Lee’s Futuristic Archaeology images show billboard-size backdrops of lush steppe contrasting with actual scenery as former nomads enact scenes of hunting, herding and Mongolian wrestling. (Photo by Daesung Lee)

These portraits reveal the incredibly humanlike expressions of a variety of apes.Through piercing eyes and finite facial details, the intimate photographs show the animals looking angry, sad, delighted and pensive. They are the works of Manuela Kulpa – an IT consultant and keen photographer from near Cologne, Germany – who shot the apes predominantly at zoos across Austria, Belgium, the Czech Republic, Germany and the Netherlands. Here: Bonobo, Azibo. (Photo by Manuela Kulpa/Caters News)

Elephants feast on fruits and vegetables during the elephant buffet prior to the start of the 2016 King's Cup Elephant Polo event in Bangkok, Thailand, 10 March 2016. The annual charity event, now in its 14th edition, runs until 13 March and will involve 18 elephants brought from tourist trekking camps in Pattaya as well as some unemployed in Surin. A total of 10 teams encompassing over 40 players will take part in the event directed at raising funds to improve the lives of elephants and elephant conservation. (Photo by Diego Azubel/EPA)