A man performs ablution using water at an old fountain before performing prayers in the old city of Algiers Al Casbah, Algeria December 3, 2015. The Algiers Casbah is a UNESCO World heritage site that includes the Sidi Ramdane mosque and former fortress, 10 centuries old. Decay from the passing years, as well as earthquake damage in 2003, leads some to consider a move to modern apartments with financial backing from the government. Others refuse to leave a neighbourhood they have called home for decades. (Photo by Zohra Bensemra/Reuters)

A woman aims a World War II machine gun at a military show during celebration of the Defenders of the Fatherland Day in St.Petersburg, Russia, Tuesday, February 23, 2016. The day, celebrated in Russia on February 23, honors the nation's military and is a nationwide holiday. (Photo by Dmitri Lovetsky/AP Photo)

Men dressed as soldiers pose with models before the opening of the Gamescom 2013 fair in Cologne,Germany, on August 23, 2013. The Gamescom convention is Europe's largest video games trade fair. (Photo by Ina Fassbender/Reuters)

Elena Reid of USA looks on with bloody face due to a cut during the Women's WIBF Flyweight Championship fight between Regina Halmich and Elena Reid at the Boerderlandhalle on December 3, 2005 in Magdeburg, Germany. (Photo by Christian Fischer/Getty Images)

“The scientists behind NASA's $2.5 billion Curiosity rover mission on Mars on Tuesday explained the nature of a tiny, gleaming "flower" embedded in Red Planet rock, and revealed where they'll be using the SUV-sized robot's drill for the first time”. – Alan Boyle via NBCNews.com

Photo: Scientists say that a “Martian flower”, seen here in an image from the Curiosity rover's Mars Hand Lens Imager, is a 2-millimeter-wide grain or pebble that's embedded in the surrounding rock. Another, darker-colored mineral grain can be seen above and to the left. (Photo by NASA)

“Most cats run away at the first sign of water but this jaguar shows that some just love to make a splash. The fierce-looking feline was spotted doing an impressive moggy paddle as it swam for meat at Taman Safari in Indonesia. The spectacular shots were captured by professional photographer, Erfin Nugroho, who was visiting the centre for endangered animals with his family”. – Richard Hartley-Parkinson. (Photo by Erfin Nugroho/Caters News)

Staff at a Scottish farm say they are “absolutely delighted” to have welcomed a baby alpaca into the world this morning, June 6, 2019. Mum, Nunavut, gave birth to the baby boy huacaya alpaca, which has not yet been named, weighing 9.6kg. Stuart Ramsay, the owner of Velvet Hall Alpacas, in Innerleithen, Scottish Borders said he was surprised when the baby was born an “unusual rose grey colour”. (Photo by South West News Service)

Youth category winner: Symphony No 5 by Giacomo Redaelli (Italy). (Photo by Giacomo Redaelli/2019 Nature Photographer of the Year)