Medic James E. Callahan of Pittsfield, Mass., gives mouth-to-mouth resuscitation to a dying soldier in war zone D, about 50 miles northeast of Saigon, June 17, 1967. Thirty-one men of the 1st Infantry Division were reported killed in the guerrilla ambush, with more than 100 wounded. (Photo by Henri Huet/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)

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)

Members of the Women's veteran movement take part in the March of Defenders of Ukraine as part of Ukraine's Independence Day celebrations, in Kyiv, Ukraine on August 24, 2020. (Photo by Gleb Garanich/Reuters)

Men walk towards law enforcement with their hands up on August 24, 2020 in Kenosha, Wisconsin. A second night of civil unrest occurred after the shooting of Jacob Blake, 29, on August 23. Blake was shot multiple times in the back by Wisconsin police officers after attempting to enter into the drivers side of a vehicle. (Photo by Brandon Bell/Getty Images)

Faithful wearing face mask pray during the Arafah prayer ceremony ahead of Eid al-Adha, at the Tehran university’s mosque in Tehran, Iran, 30 July 2020. Iran will not hold the Eid al-Adha prayers and ceremonies over the coronavirus (COVID-19) crisis in the country. (Photo by Abedin Taherkenareh/EPA/EFE)

Two guests pose prior to the Dolce & Gabbana 2021 women's spring-summer ready-to-wear collection during the Milan's fashion week in Milan, Italy, Wednesday, September 23, 2020. (Photo by Luca Bruno/AP Photo)

In a photo taken on November 4, 2020 visitors wearing traditional Korean hanbok dress walk beneath yellow ginko leaves in a courtyard at Gyeongbokgung palace in Seoul. (Photo by Ed Jones/AFP Photo)