Kevin Kvasnicka (L) and Jesse Gonzales openly carry firearms as they watch U.S. Republican presidential nominee Donald Trump speak on a big screen television along East 4th street during the Republican National Convention in Cleveland, Ohio, U.S., July 21, 2016. (Photo by Adrees Latif/Reuters)

Supporters of former Democratic presidential candidate Bernie Sanders hold up posters at a “Black Men For Bernie” rally to gain support for third party candidates and protest the DNC during the 2016 Democratic National Convention on July 27, 2016 in Philadelphia, Pennsylvania. (Photo by Patrick T. Fallon/AFP Photo)

An athlete pulls a 15-tonne truck during a Truck-Pull event marking the upcoming Independence Day in the Belarus capital Minsk, on July 3, 2014. The former Soviet nation celebrates its Independence Day on July 3 in memory of the end of Belarus occupation by Nazi Germany troops during the Red Army main summer offensive in 1944. (Photo by Sergei Gapon/AFP Photo)

“In 1967, Zhang Yaxin was 34 and working as a photojournalist at China’s state-controlled Xinhua News Agency when he was assigned to a top-secret government project. He was to be the official photographer of a new arts program led by Chairman Mao and his wife – the Model Operas. Though he was not to know it then, Zhang would spend the next seven years documenting the evolution of one of the most dramatic and elaborate attempts to redefine artistic sensibilities in modern art history”. – Chengcheng Jiang via TIME. Photo: Raid on the White Tiger Regiment, 1971. (Photo by Zhang Yaxin/Courtesy See+ Gallery, Beijing)

Lady Gaga performs at Staples Center on August 11, 2010 in Los Angeles, California. (Photo by Jason Merritt/Getty Images)

“Life-size humanoid robot BERTI (Bristol EluMotion Robotic Torso number 1 or RT-1) is a self contained, fully automated Robotic Torso, designed and built by Elumotion to provide a robotic platform based on human anatomy. RT-1 is a highly articulated manipulating platform and includes novel dexterous hands that allow emulation of human gesturing”. – Elumotion.com

Photo: BERTI the robot interacts with a Sony AIBO robot dog at The Science Museum's Antenna Gallery on February 17, 2009 in London. (Photo by Peter Macdiarmid/Getty Images)

A ballet dancer stretches backstage during Nacho Duato's “The Nutcracker” at the Mikhailovsky Theatre in St. Petersburg, Russia November 21, 2015. For theatregoers in St Petersburg, Nacho Duato's “The Nutcracker” demonstrates the global appeal of a Christmas classic. When the curtain rises at the Mikhailovsky Theatre, among the oldest opera and ballet houses in Russia, it's the culmination of hundreds of hours of toil and sweat by dancers, costume makers, set designers and musicians playing the famous score by Pyotr Tchaikovsky. (Photo by Grigory Dukor/Reuters)

Behaviour: Mammals category. Giant Gathering by Tony Wu, USA. Dozens of sperm whales mingled noisily off Sri Lanka’s northeast coast, stacked as far down as Tony could see. This was a congregation of dozens of social units, like a gathering of the clans. Aggregations like this could be a critical part of the whales’ rich social lives but are rarely reported. Some two thirds of the population was wiped out before commercial whaling was banned in 1986. This kind of major gathering could be “a sign that populations are recovering”, says Tony. (Photo by Tony Wu/Wildlife Photographer of the Year 2017)