In this May 8, 2015 photo, sisters Zoraida Infante, left, and Graciela Trujillo pray on Fishermen's Beach before therapeutic swimming in the Pacific Ocean in Lima, Peru. Under overcast skies, the bathers practice thalassotherapy, which derives from the Greek “thalasso”, for “sea”, and draws on the ocean's healing properties. (Photo by Rodrigo Abd/AP Photo)

Two female revelers engage in a beer drinking contest in the Hacker Pschorr tent on the first day of the 2017 Oktoberfest beer fest on September 16, 2017 in Munich, Germany. Oktoberfest is the world's largest beer celebration and typically draws over six million visitors over its three-week run. Oktoberfest includes massive beer tents, each run by a different Bavarian brewer, as well as amusement rides and activities. (Photo by Philipp Guelland/Getty Images)

In this February 19, 2017 photo, a couple dances during the “If you don't give me....then you lend me” Carnival street party on Ipanema beach, in Rio de Janeiro, Brazil. The typical view of Carnival in Brazil is anything goes, with no headdress too big, no outfit too small, no song too ribald, but this year some organizers of the world's best known party are drawing the line at lyrics that are sexist, homophobic or racist. (Photo by Silvia Izquierdo/AP Photo)

Soldiers of the 70th division of the American 7th Army hold up a Nazi flag and a portrait of Adolf Hitler, taken during the World War II capture of Saarbrucken. (Photo by Horace Abrahams/Keystone/Getty Images). 22nd March 1945

Actress Tang Wei poses at the “Wu Xia” portrait session during the 64th Annual Cannes Film Festival on May 15, 2011 in Cannes, France. (Photo by Andreas Rentz/Getty Images)

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)