A waste picker unloads garbage at a waste transfer station in Bamako, Mali, August 19, 2018. In the Malian capital of Bamako, donkey carts driven by young men like 19-year-old Arouna Diabate play a vital role battling the fast-growing city's waste problem. Every morning before dawn, Diabate hitches his donkey to a cart and sets off on his rounds, going door-to-door to collect household garbage which he delivers to a local waste transfer station for a monthly salary of around $35. “I won't be picking up trash with a donkey cart for the rest of my life, but for now people appreciate us because we help clean up the homes of Bamako”, Diabate said. (Photo by Luc Gnago/Reuters)

“DC3 Wreck”. A capture of a US military DC3 plane wreck at the southern black beach in Iceland. Photo location: Iceland. (Photo and caption by Naian Feng/National Geographic Photo Contest)

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)

Ukrainians jump over a fire in Kiev, Ukraine, 06 July 2017, as they celebrate the traditional pagan holiday of Ivana Kupala. Ivana Kupala is celebrated, during the summer solstice, on the shortest night of the year, marking the beginning of summer and is celebrated in Ukraine, Belarus, Poland and Russia on the night of 06 July. People sing and dance around bonfires, play games and perform traditional rituals. Young people jump over bonfires in order to test their bravery. Couples holding hands jump over the flames to test their love. If the couple does not succeed it is predicted to split up. Traditionally, children and young unmarried women wear wreaths of wild flowers on their heads to symbolize purity. (Photo by Sergey Dolzhenko/EPA)

A damaged vehicle is seen next to the ring road, around Skopje, near the village of Stajkovci, Skopje, The Former Yugoslav Republic of Macedonia, 08 August 2016. At least 21 people have died and more than 100 are injured in the heavy rain storm that hit the Macedonian capital Skopje late Saturday night causing severe damage to the roads and house infrastructure. More than 80 vehicles were hit by landslides at Skopje's ring road. The highway remains closed. The government announced a 15-day state of emergency in the Skopje and Tetovo region. (Photo by Georgi Licovski/EPA)

A Baby sumatran orangutan (Pongo abelii) plays around in a tree as they train at Sumatran Orangutan Conservation Programme's rehabilitation center on November 12, 2016 in Kuta Mbelin, North Sumatra, Indonesia. The Orangutans in Indonesia have been known to be on the verge of extinction as a result of deforestation and poaching. Found mostly in South-East Asia, where they live on the islands of Sumatra and Borneo, the endangered species continue to lose their habitat as a result of corporate expansion in a developing economy. Indonesia approved palm oil concessions on nearly 15 million acres of peatlands over the past years and thousands of square miles have been cleared for plantations, including the lowland areas that are the prime habitat for orangutans. (Photo by Ulet Ifansasti/Getty Images)

A man runs away during a police round up of suspected drug addicts in Kabul, Afghanistan December 27, 2015. Afghan officials have opened a new drug treatment centre in an abandoned NATO military base in Kabul, in the latest attempt to stamp out the country's massive problem of drug abuse. Camp Phoenix, a former training camp on the edges of Kabul set up by the U.S. army in 2003, will take in around 1,000 homeless drug addicts who will receive food, medical attention and treatment, said Public Health Minister Ferozuddin Feroz. (Photo by Ahmad Masood/Reuters)

An astonishing set of snaps of a thrill-seeker's sky-high catwalk show on the edge of some of the world's tallest buildings has turned her into a social media sensation. Daredevil Angelina Nikolau, 23, from Russia, has spent weeks travelling around China and Hong Kong posing for jaw-dropping skyscraper selfies hundreds of feet above the ground. Her vertigo inducing results – uploaded to Instagram – have made her an instant star on the internet. (Photo by Kirill Oreshkin/CEN)