A participant falls on vintage skis during a traditional historical ski race in the northern Bohemian town of Smrzovka February 21, 2015. (Photo by David W. Cerny/Reuters)

Vickie Leuenberger (L) practices with a mermaid tail with AquaMermaid founder Marielle Chartier Henault in a pool in Montreal, February 19, 2015. The school teaches kids and adults how to swim wearing mermaid tails, and offers mermaid-themed parties. (Photo by Christinne Muschi/Reuters)

The pit lane is reflected in the visor of a Mercedes Formula One pit crew member during the second practice session of the Australian F1 Grand Prix at the Albert Park circuit in Melbourne March 13, 2015. REUTERS/Brandon Malone

Soldiers stop to buy goods at the main market of Diffa, Niger, March 23, 2015. Diffa is where Nigerien and Chadian troops fighting insurgent group Boko Haram are based at. (Photo by Joe Penney/Reuters)

A reveller walks through the streets in the early hours during traditional May Day celebrations in Oxford, Britain, May 1, 2015. (Photo by Dylan Martinez/Reuters)

Labourers work at the installation site of Liquefied Petroleum Gas (LPG) pipeline on May Day or Labour Day in Chandigarh, India, May 1, 2015. (Photo by Ajay Verma/Reuters)

Women look at a collapsed building caused by earthquakes, in Bhaktapur, Nepal, May 18, 2015. Nepal is facing billions in reconstruction costs with almost 745,600 buildings and homes damaged or destroyed, including at least 87,700 in the capital, according to Nepal's emergency authority. (Photo by Ahmad Masood/Reuters)

Activists from People for the Ethical Treatment of Animals (PETA) promoting a vegan diet are pictured as people drive past in Los Angeles, California May 21, 2015. (Photo by Mario Anzuoni/Reuters)