Workers demonstrate outside the factory of Hua Yang Printing Holdings Co Ltd on October 30, 2007 in Shenzhen of Guangdong Province, China. Over 1,000 workers of the company have blocked the 107 State Highway where the firm is located, to protest against their employer, who owed half a month's salary to the workers. (Photo by China Photos/Getty Images)

Ice covered leafs are pictured on a tree near Amstall in northern Austria, December 2, 2014. Freezing fog and rain covered parts of the region with ice, causing blocked roads due to fallen trees and closed schools for security reasons, local media report. (Photo by Heinz-Peter Bader/Reuters)

A dog wears “The Flash” costume for a carnival pet parade in Rio de Janeiro, Brazil, Sunday, January 31, 2016. People dressed their pets up for the annual block parade held near Copacabana beach. (Photo by Leo Correa/AP 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)

Students wearing mask hold hands to surround the St. Stephen's Girls' College in Hong Kong, Monday, September 9, 2019. Thousands of demonstrators in Hong Kong urged President Donald Trump to “liberate” the semiautonomous Chinese territory during a peaceful march to the U.S. Consulate on Sunday, but violence broke out later in the business and retail district as police fired tear gas after protesters vandalized subway stations, set fires and blocked traffic. (Photo by Kin Cheung/AP Photo)

Two men help each other cross a street covered in deep mud in Copiapo, Chile, Thursday, March 26, 2015. Unusually heavy thunder storms and torrential rains that began on Tuesday have blocked roads, caused power outages and affected some 600 people on this normally dry region. (Photo by Aton Chile/Marcelo Hernandez/AP Photo)

Traditional miners carry sulphur on the Ijen volcano complex on May 25, 2009 outside Banyuwangi, East Java, Indonesia. Miners carry the solidified yellow sulphur blocks from the crater floor to the rim for as many hours a day as they can tolerate, paid by the kilogram of sulphur they extract. The average wage is USD $.05 per kilogram of sulphur and a worker, depending on his strength and stamina, carry on average 3 baskets of 70-80kg per day, earning him around USD $11. (Photo by Ulet Ifansasti/Getty Images)

An anti-coup protester holds a Burkinabe flag in Ouagadougou, Burkina Faso, September 18, 2015. Security forces in the capital of Burkina Faso fired in the air on Friday to disperse demonstrators who burned tyres and blocked neighborhood streets to protest at a military coup this week that derailed a democratic transition. The head of a military junta in Burkina Faso which took power on Thursday has freed interim President Michel Kafando and two of his ministers, state television said on Friday. (Photo by Joe Penney/Reuters)