A hippopotamus performs during a show at the circus in Krasnoyarsk, Siberia, Russia, July 7, 2016. (Photo by Ilya Naymushin/Reuters)

Team Alberta skip Kevin Koe makes a shot during the 10th draw against team British Columbia at the Brier curling tournament in Brandon, Manitoba, Tuesday, March, 5, 2019. (Photo by Jonathan Hayward/The Canadian Press via AP Photo)

A vintage car sits in flood water on March 20, 2019 in Hamburg, Iowa. Although flood water in the town has started to recede many homes and businesses remain surrounded by water. Several Midwest states are battling some of the worst flooding they have experienced in decades as rain and snow melt from the recent “bomb cyclone” has inundated rivers and streams. At least three deaths have been linked to the flooding. (Photo by Scott Olson/Getty Images)

A dachshunds is dressed in an outfit as it is shown off during the eighth annual Dachshunds Parade in Saint Petersburg, Russia on May 25, 2019. (Photo by Olga Maltseva/AFP Photo)

Children enjoy a sledge ride past ice swimming fans at the Zalew Zegrzynski lake in Nieporet, Poland, Sunday, February 25, 2018. A cold wave hit Poland with the temperature minus 8 degree Celsius (17.6 Fahrenheit) during the day and dropping to minus 16 degree Celsius (3.2 Fahrenheit) in the night in central Poland. (Photo by Alik Keplicz/AP Photo)

In this 2017 photo provided by Simon Pierce, Jonathan Green checks on a fin-mounted satellite tag on a whale shark in the Galapagos Islands area of Ecuador. Despite typically being bigger than a double-decker bus, the elusive whale shark has only tiny, almost useless teeth. It's also one of the least understood animals in the ocean. (Photo by Simonjpierce.com via AP Photo)

Women dancing at the disco club Xenon in New York City, USA in 1978. Xenon was a popular disco in Manhattan in the late 1970s and early 1980s. It was the only nightclub popular enough to compete with Studio 54. (Photo by Waring Abbott/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)