Vultures gather to eat waste in Bica beach, on the banks of the Guanabara Bay, with the Sugar Loaf mountain in background, 500 days ahead the Rio 2016 Olympic Games in Rio de Janeiro March 24, 2015. As part of its Olympic bid, Rio promised to clean up 80 percent of the bay for the games. But local government officials have already admitted that a cleanup by 2016 is not achievable. Despite millions of dollars of investment over the years, the bay still stinks of sewage. Sailors who visited the city for test events complained of a floating sofa and a dead dog in the water. (Photo by Ricardo Moraes/Reuters)

Traditional dancers from southern state Tamil Nadu prepare themselves as they wait to perform during a press preview of displays being featured for the upcoming Republic Day parade in New Delhi on January 22, 2019. The Republic Day is an annual showcase of India's military hardware and cultural diversity. India celebrates its 70th Republic Day on January 26. (Photo by Sajjad Hussain/AFP Photo)

The National Geographic Photo Ark is a travelling exhibition of photographer Joel Sartore’s quest to create a photo archive of biodiversity around the world. So far, Sartore has captured studio portraits of more than 6,000 species – a number that he hopes to double. On 1 July, the ark will open at Melbourne zoo – the first time it has been exhibited in the southern hemisphere. More than 50 portraits will be on display, including many of Australian endangered animals being protected by programs at the zoo itself. These captions have been edited from text supplied by Melbourne zoo. Here: Barking owl. (Photo by Joel Sartore/National Geographic Photo Ark/The Guardian)

People watch police destroy confiscated illegal firecrackers in Shenyang, Liaoning province, China, January 29, 2016. (Photo by Reuters/Stringer)

Auditioning performers follow resident choreographer Erik Sorensen, center back, at the Sydney Dance Company in a routine during castings in Moulin Rouge's current show “Féerie”, in Sydney, Australia, Thursday, July 28, 2016. The show's artistic team is in Australia to choose new talent to perform with one of the most famous cabarets that has been illuminating Paris since 1889. (Photo by Rob Griffith/AP Photo)

Models prepare backstage before a presentation as part of Fashion Weekend Plus Size Summer 2015 collection show in Sao Paulo, July 25, 2015. (Photo by Nacho Doce/Reuters)

A truffle is seen on a table in Alba, north-western Italy November 11, 2013. Located in the heart of the Langhe – the hilly southern area of Italy's northwestern Piedmont region – Alba is the country's capital of white truffles, a variety of the prized fungus which grows underground. Truffles are found two to eight inches (5-20cm) below the ground near the roots of trees. They give off an odour which lasts for a limited period of time and can be detected with the assistance of well-trained dogs and experienced hunters. Output of white truffles, which are not cultivated and only grow naturally in forests, has fallen in Italy over the past few years, largely because climate change has brought a damaging mix of drought and torrential rains. (Photo by Stefano Rellandini/Reuters)

A young Thai man jumps in the air and cheers as his rocket takes off at the Bun Bang Fai Rocket Festival on May 10, 2015 in Yasothon, Thailand. During the Bun Bang Fai rocket festival, Thai residents launch enormous home-made rockets into the air to gain Buddhist merit and to celebrate the beginning of the rainy season. (Photo by Taylor Weidman/Getty Images)