(L-R) Edmea Pereira, 69, Elsa Rodrigues, 61, and Osmidio Conde, 71, take part in their surf class in Santos, Sao Paulo state, Brazil, March 16, 2016. When work is up, surf is up in Brazil, as a group of retired citizens take to the waves in keep-fit, keep-young sessions at a surf school in the city of Santos. The classes are run for free, three times a week at the Cisco Arana school, which aims to prove that age is just a number. (Photo by Nacho Doce/Reuters)

A young man with an amputated leg poses for a photograph standing by his broken artificial limb in the rebel-controlled area of Maaret al-Numan town in Idlib province, Syria March 20, 2016. Two university students forced to interrupt their studies have learnt to make and fit hundreds of new limbs in the past four years in opposition-held areas of Syria. A mobile clinic operating from a truck has gone some way to improve access to treatment. While most patients are between 15 and 45, the clinic also helps children and the elderly with replacement limbs. (Photo by Khalil Ashawi/Reuters)

Models, painted by bodypainting artist Alex Hansen from Brasil and Benoit Botella from Guadaloupe, pose for a picture at the 21st World Bodypainting Festival 2018 on July 14, 2018 in Klagenfurt, Austria. (Photo by Didier Messens/Getty Images)

Londoners enjoying the magnificent sight of sun setting perfectly in the middle of London Eye as seen from Greenwich Park in London, England on the warmest day of the year on April 19, 2018. (Photo by London Viewpoints/Rex Features/Shutterstock)

These heartbreaking photo show a confused family of elephants attempting to navigate a railway line built straight through their habitat on October 16, 2012. Taken by Biplab Hazra in Bishnupur, India, the images show the extreme lengths the inhabitants of the town go to to deter elephants from damaging their crops and property. As the images show, villagers often resort to extreme tactics in an effort to drive the elephants out with one shocking photograph revealing firebombs being launched at a mother and calf as they cross the road. Elephants encroaching out of their habitats is an increasingly common occurrence with deforestation in much of India. (Photo by Biplab Hazra/Caters News Agency)

A man stands near smoke billowing from a brick kiln in Karachi, Pakistan, 14 December 2018. According to the UN report, carbon dioxide (CO2) emissions have increased for the first time in four years. The United Nations Conference COP24, held in Katowice, Poland, until 14 December 2018, searches for a common position in the fight against climate change. (Photo by Shahzaib Akber/EPA/EFE)

A worker spreads paddy crop for drying in a rice mill complex on the outskirts of Ahmedabad February 3, 2011. (Photo by Amit Dave/Reuters)

Sniper rifles sit on display for sale at the “Ready Gunner” gun store in Provo, Utah, U.S., June 21, 2016. (Photo by George Frey/Reuters)