Earlier this year, Belgian film-maker and artist Vincent Bal stumbled upon an uncanny resemblance to an elephant in the shadow of his tea cup. This gave him the idea for Shadowology, a series of doodles that interact with the shadows of simple, everyday objects: a banknote, some ice cubes and a flower, for example, can turn into a church, a woman and a hippy. “I draw a few lines and I get my image. It’s really the shadows that inspire me”, Bal says. Here: “Stonedog”. (Photo by Vincent Bal/The Guardian)

Labourers who work nearby nap on a road as cars drive past in Chongqing Municipality, July 23, 2013. (Photo by Reuters/Stringer)

Artist Princess Tarinan von Anhalt throws paint into the flow of air coming from the engine of Flexjet’s Learjet 40 XR engine to create a painting on a canvas at Signature Flight Support in West Palm Beach, Florida. The artist associated with the Jet Art Group used the help of Flexjet and their plane to spray paint on a canvas to create distinctive paintings to celebrate the 50th anniversary of Learjet. (Photo by Thomas Cordy/The Palm Beach Post)

Jo-Anne McArthur’s book of photographs puts the spotlight on ethics of zoos around the world. Accompanied by essays by Born Free Foundation’s Virginia McKenna and philosopher Lori Gruen, the images and stories are also shared online through “A Year of Captivity”. Here: Asian Elephant, Denmark, 2016. (Photo by Jo-Anne McArthur/Born Free Foundation/The Guardian)

A conductor (C) collects fares from candy floss sellers as they travel in a tram to a marketplace early morning in Kolkata, India, December 23, 2015. (Photo by Rupak De Chowdhuri/Reuters)

In this Sunday, May 29, 2016 photo, fighters take a selfie while firing artillery during fight against Islamic State militants in Fallujah, Iraq. Iraqi forces this week pushed into the city's southern sections after securing surrounding towns and villages more than 50,000 people are believed to be trapped inside the Sunni majority city, about 65 kilometers (40 miles) west of Baghdad. (Photo by Anmar Khalil/AP Photo)

Venezuela's acting President and presidential candidate Nicolas Maduro kisses a painting of late Venezuelan president Hugo Chavez during a campaign rally in the state of Vargas April 9, 2013. Venezuelans will hold presidential elections on April 14. Maduro promised on Tuesday to hike Venezuela's minimum wage by about 40 percent if he is elected in a weekend vote to replace late socialist leader Chavez. (Photo by Carlos Garcia Rawlins/Reuters)