Californian photographer and conservationist Octavio Aburto had spent years photographing the school in Cabo Pulmo National Park, Mexico – and had been trying to capture this exact shot for three years. “Together with my friend David Castro, we were diving with a large group of Bigeye travellies at Cabo Pulmo National Park, Mexico. Thousands of fish forming a ball during the reproduction courtship. In the afternoon, these fish congregate to form a large spawning aggregation around the reefs of the National Park”. (Photo and caption by Octavio Aburto)

This year's Republican National Convention and Democratic National Convention both saw passionate delegates in outrageous costumes – but that's where the similarities mostly end. Reuters photographer Jim Young gives a look at what it's like to be on the convention floor and talks to the delegates who make the conventions memorable. (Photo by Jim Young/Reuters)

Romanian military doctors and medical students sit on a bus behind steamy windows before the National Day parade in Bucharest, Romania, Thursday, December 1, 2016. Military planes and helicopters flew over the Romanian capital Thursday as thousands turned out to celebrate the national day, marking the date when the country reunified with Transylvania in 1918. (Photo by Vadim Ghirda/AP Photo)

A woman dressed in a dirndl, a kind of traditional Bavarian clothing, jumps into Lake Schlier on July 30, 2006 in Schliersee, Germany. The event called "Dirndlfliegen" ("Dirndl Flying") was sponsored by a local fashion store and a big Austrian Dirndl manufacturer. While these kind of events had been held in Austria before, this was the first of its kind in Germany. 29 women and one man wearing a wig participated in the event that held a new Dirndl as the grand prize. (Photo by Andreas Leder/Getty Images)

“Today, we take photography for granted. Anyone can take a photograph simply by pressing a button. Yet, it was not always so simple. The invention of photography was announced in 1839, but during its first fifty years taking a photograph was a complicated and expensive business. In 1888, all this was to change following the appearance of a camera that was to revolutionize photography. Popular photography can properly be said to have started 120 years ago with the introduction of the Kodak”. – The UK National Media Museum. Photo: Two men on the deck of a ship, about 1890. (Photo by Collection of National Media Museum/Kodak Museum)

Photographer Maurizio Pignotti, 46, spends all night in freezing temperatures painstakingly shooting the breathtaking crystal-clear stars. He uses a technique where he merges together anywhere between 80 and 450 shots to create what he describes as a “rainbow of stars”. Space-lover Maurizio, captures the star trails on the borders of the Adriatic Sea – including the Sibillini Mountains National Park, the Conero National Park, and the Gargano National Park. (Photo by Maurizio Pignotti/Caters News)

Masooma Alizada (L) and Frozan Rasooli (R), members of Afghanistan's Women's National Cycling Team prepare a bicycle before training on the outskirts of Kabul February 20, 2015. Afghanistan's Women's National Cycling Team has been breaking new ground for women's sports and pushing the boundaries of what is – and is not – acceptable for young women in the conservative Muslim country. (Photo by Mohammad Ismail/Reuters)

A female member of Romania's military adjusts her hat before taking part in the national day military parade in Bucharest, Romania, Friday, December 1, 2017. Thousands of Romanian troops staged a military parade to celebrate Romania's national day, but key politicians didn't attend, signaling tensions between the president and the ruling left-wing coalition over plans to revamp the justice system. (Photo by Vadim Ghirda/AP Photo)