Devotees ride on the roof of a train as they return to the city after attending the final prayers on the first phase of Bishwa Ijtema in Dhaka January 11, 2015. Hundreds of thousands of pilgrims congregated in the Bangladeshi capital Dhaka as the first phase of this year's Bishwa Ijtema, one of the biggest Islamic gatherings in the world after the Haj in Saudi Arabia, came to an end. (Photo by Reuters/Stringer)

Anand Varma, a U.S. photographer working for the National Geographic, won the First Prize in the Nature Category, Stories, of the 2015 World Press Photo contest with his series of pictures, which includes this one of spores of a fungus landing on an ant, penetrating its exoskeleton and entering its brain, compelling the host to leave its normal habitat on the forest floor and scale a nearby tree, in this picture taken January 22, 2014 and released by the World Press Photo on February 12, 2015. (Photo by Anand Varma/Reuters/National Geographic/World Press Photo)

A woman sits on a terrace at Tiki hostel in Cantagalo favela, in Rio de Janeiro, Brazil, April 16, 2016. Hostels in a few of Rio's more than 1,000 slums serve not only as a cheap housing alternative for the more adventurous among the estimated 500,000 foreign tourists expected to arrive for the Olympics in August. The establishments also open up the rich culture of the city's shantytowns for travellers, giving them a glimpse into once “no-go” areas where about one-fifth of Rio's population lives. (Photo by Pilar Olivares/Reuters)

A girl jumps over a campfire while celebrating Ivan Kupala Night, a traditional Slavic holiday not far from Kiev on July 6, 2013. During the celebration, originating in pagan times, people plait wreaths, jump over fires, and swim naked. (Photo by Sergei Supinsky/AFP Photo)

Actor Bryan Cranston engages Julia-Louis Dreyfus in a prolonged kiss as she takes the stage to accept the award for Outstanding Lead Actress In A Comedy Series for her role in HBO's “Veep” during the 66th Primetime Emmy Awards in Los Angeles, California August 25, 2014. (Photo by Mario Anzuoni/Reuters)

Revellers attend the Victorian Picnic during the Wave and Goth festival in Leipzig, Germany, May 22, 2015. The annual festival, known in Germany as Wave-Gotik Treffen (WGT), features over 100 bands and artists in venues all over the city playing Gothic rock and other styles of the dark wave music subculture. One of the biggest of its kind, the event attracts a regular audience of up to 20,000, the organisers said. (Photo by Hannibal Hanschke/Reuters)

The Hubble Space Telescope is shown following its release from the space shuttle Discovery Wednesday, February 19, 1997. The Hubble Space Telescope, one of NASA'S crowning glories, marks its 25th anniversary on Friday, April 24, 2015. With more than 1 million observations, including those of the farthest and oldest galaxies ever beholden by humanity, no man-made satellite has touched as many minds or hearts as Hubble. (Photo by AP Photo/NASA)

Meghan Puhr participates in a virtual realty presentation during an Intel news conference before CES International, Wednesday, January 4, 2017, in Las Vegas. (Photo by John Locher/AP Photo)