A handout photograph provided by Brian Kubicki of Costa Rican Amphibian Research Center on 26 April 2016 shows a “Crystal frog”, Hyalinobatrachium dianae (H. diane). This frog was discovered by US biologist Brian Kubicki and Costa Ricans Stanley Salazar and Robert Puschendorf in a rainy forest of Costa Rican caribbean after 40 years without notice of any new example of this kind. (Photo by Brian Kubicki/EPA/Costa Rican Amphibian Research Center)

A young girls holds a ballot during the Greek referendum in Athens on July 5, 2015. Greek voters headed to the polls today to vote in a historic, tightly fought referendum on whether to accept worsening austerity in exchange for more bailout funds, in a gamble that could see it crash out of the euro. (Photo by Aris Messinis/AFP Photo)

In this June 29, 2015 photo, hairdresser Loavia Bienaime, 30, sits on her bed as she prepares to begin her day in the room her family occupies in an government office building that was damaged in the 2010 earthquake in Port-au-Prince, Haiti. Bienaime's husband, Jimmy Bellefleur, used his skill as an electrician to connect the abandoned building to the power grid, and has repaired broken televisions, fans, and a blender for the family to use. (Photo by Rebecca Blackwell/AP Photo)

Children pat an elephant at the mobile Diva circus in the town of Molodechno, some 70 kilometers northwest of Minsk on September 3, 2015. (Photo by Sergei Gapon/AFP Photo)

A paddler races in a giant pumpkin during the annual regatta on Lake Pisiquid in Windsor, Nova Scotia, Sunday, October 11, 2015. Participants hollow out the massive gourds and pilot them across the 500 meter course. (Photo by Andrew Vaughan/The Canadian Press via AP Photo)

Indigenous women from the Kamayura tribe take part in a demonstration of Huka Huka fight at the first World Games for Indigenous Peoples in Palmas, Brazil, October 29, 2015. (Photo by Ueslei Marcelino/Reuters)

A woman jumps in the air as she poses for a photo during New Year celebrations in the Manhattan borough of New York, January 1, 2016. (Photo by Carlo Allegri/Reuters)

A South Sudanese model applies make-up during the Festival of Fashion and Arts for Peace in Juba August 9, 2014. (Photo by Andreea Campeanu/Reuters)