Protesters shield themselves as police beat them with sticks during a violent demonstration near the India Gate against a gang rape and brutal beating of a 23-year-old student on a bus last week, in New Delhi, India, December 23, 2012. The attack last Sunday has sparked days of protests across the country. (Photo by Kevin Frayer/Associated Press)

Over just 18 months, Sir Charles Barkley, a French bulldog from Seattle, Washington, has become an internet sensation. His daily photos have attracted him an Instagram following of more than 115,000 fans. Photo: Sir Charles Barkley enjoys some play park time. (Photo by Caters News)

“Just hanging out”. As full autumn hits the valley of Hallingdal in Norway, this bear chills out in a tree which seems to barely cover its weight. Photo location: Flå, Hallingdal, Norway. (Photo and caption by Jorgen Tharaldsen/National Geographic Photo Contest)

These photographs are the work of urban explorer Dr Bradley Garrett who made headlines back in 2012 when he posted a series of snaps from the top of The Shard skyscraper while it was still under construction. Garrett, now a researcher at the University of Oxford, took these shots during his time with the London Consolidation Crew (LCC), a loose collection of urban explorers based in the English capital. Photo: Bradley Garrett stands on the edge of the Ritz-Carlton Chicago as lightning strikes in the distance in Chicago, US. (Photo by Bradley L. Garrett/Barcroft Media)

A villa privately built on the rooftop of a residential building in downtown Beijing has prompted complaints from neighbours living below. Professor Zhang, the villa owner, has been instructed to tear down the illegal building, according to the property managers. (Photo by Mark Ralston/AFP Photo)

Reuters photographer Carlos Barria recently spent time in Shanghai, China, the fastest-growing city in the world. A week ago, he took this amazing shot, recreating the same framing and perspective as a photograph taken in 1987, showing what a difference 26 years can make. (Photo by Carlos Barria/Reuters/Stringer via The Atlantic)

Photographer Pol Kurucz’s vivid collection of photos explores issues faced by black Brazilian women, from political misrepresentation to unrealistic beauty standards. Kolor Collective is a Rio de Janeiro-based creative group that challenges the struggle faced by black women in Brazil through theatrical and provocative art. It was founded in 2015 by Franco-Hungarian photographer Pol Kurucz, who often touches on his own experiences of discrimination to call out sensitive social problems. (Photo by Kolor Art Collective/The Guardian)

Wedges of an orange generate enough current and electrical juice – 3.5 volts – to power an LED. The fruit’s citric acid helps electrons flow from galvanized nails to copper wire in this 14-hour exposure. This image was published in September’s Visions of Earth, a trio of photos that appear in each issue of National Geographic. (Photo by Caleb Charland/National Geographic)