Cambodian children sleep on a pavement at a park in Phnom Penh on July 8, 2016. (Photo by Tang Chhin Sothy/AFP Photo)

People watch a forest fire in Funchal, Madeira Island, Portugal, 09 August 2016. The fire has led to the evacuation of 400 people. Portugal remains on high alert as a wave of wildfires has swept the country with around 350 isolated fires affecting swathes of the countryside. (Photo by Gregório Cunha/EPA)

A baby elephant eats in a swamp in Amboseli national park, Kenya, March 19, 2017. (Photo by Goran Tomasevic/Reuters)

An Iraqi special forces soldier wears a rose in his body armor as troops move from the Yarmouk neighborhood to take another district from Islamic State militant control in Mosul, Iraq, Wednesday, April 12, 2017. (Photo by Maya Alleruzzo/AP Photo)

A man carries his dog as he prays during Vesak Day, an annual celebration of Buddha's birth, enlightenment and death, at Wat Yai Chai Mongkhon temple in Ayutthaya, Thailand, May 10, 2017. (Photo by Athit Perawongmetha/Reuters)

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)

A street side fruit vendor has his face covered as a precaution against the coronavirus in Kolkata, India, Tuesday, July 21, 2020. With a surge in coronavirus cases in the past few weeks, state governments in India have been ordering focused lockdowns in high-risk areas to slow down the spread of infections. (Photo by Bikas Das/AP Photo)

Garbage men race on their tricycles along the track during the garbage men bicycle race at Ban Jelacic square in Zagreb, Croatia, 19 August 2020. Zagreb's authorities organised a street festival named “Cest is the best” despite the coronavirus pandemic in Croatia with some 219 infected people. (Photo by Antonio Bat/EPA/EFE)