A machine works on a Rio 2016 Olympic medal at the Casa da Moeda do Brasil (Brazilian Mint) in Rio de Janeiro, Brazil, June 28, 2016. The Casa da Moeda do Brasil is the Brazilian mint, owned by the Brazilian government and administratively subordinated to the Ministry of Finances. It was established in 1694. (Photo by Sergio Moraes/Reuters)

The Rio de Janeiro Olympics kick off on August 5 for some two weeks of competitive games drawing athletes as well as audiences from around the world. As they prepare to cover the event, Reuters photographers look back on their favourite pictures from past Olympics where they captured the action on the ground as well as the participants' tears and joy that followed. (Photo by Lucy Nicholson/Reuters)

Macaque monkeys crowd together in their cage at a monkey farm on February 3, 2016 in Xinye county, Henan province, China. The area boasts a centuries-long and lucrative history of raising and training monkeys for performance. In Xinye, villagers are seeing an increase in business with the lunar calendar's “Year of the Monkey”. Farmers say most of the monkeys are bred and raised for domestic zoos, circuses, and performing groups, but add that some are also sold for medical research in China and the United States. Despite the popularity of the tradition, critics contend the training methods and conditions constitute animal cruelty. (Photo by Kevin Frayer/Getty Images)

Performers of circus company Circa perform during a photocall for the Edinburgh Festival Fringe on Calton Hill on August 1, 2017 in Edinburgh, United Kingdom. (Photo by Murdo MacLeod/The Guardian)

McMurdo Station is a U.S. Antarctic research centre located on the southern tip of Ross Island, which is in the New Zealand-claimed Ross Dependency on the shore of McMurdo Sound in Antarctica. It is operated by the United States through the United States Antarctic Program, a branch of the National Science Foundation. The station is the largest community in Antarctica, capable of supporting up to 1,258 residents, and serves as the United States Antarctic science facility. All personnel and cargo going to or coming from Amundsen–Scott South Pole Station first pass through McMurdo.

“Sky burial or ritual dissection was once a common funerary practice in Tibet wherein a human corpse is cut in specific locations and placed on a mountaintop, exposing it to the elements or the mahabhuta and animals – especially to birds of prey. The location of the sky burial preparation and place of execution are understood in the Vajrayana traditions as charnel grounds. In Tibet the practice is known as jhator, which literally means, «giving alms to the birds»”. – Wikipedia

Photo: A burial master chops bones of a body to feed vultures during a celestial burial ceremony on April 19, 2006 in Dari County of Guoluo Prefecture, Qinghai Province, northwest China. Celestial burial is a traditional funeral of Tibetan people, which began in the 7th century. (Photo by China Photos/Getty Images)

A man presents a self-made robot that local media reported is able to carry a person, in Heihe, Heilongjiang province, China, April 5, 2017. (Photo by Reuters/China Daily)

Swiss police officers stand beside of mock gates of the NEAT Gotthard Base Tunnel inside the event hall for the upcoming opening ceremony near the town of Erstfeld, Switzerland May 31, 2016. The celebrations of the opening of the Gotthard Base Tunnel will start on June 1, 2016. With a length of 57 km (35 miles) crossing the Alps, the Gotthard Base tunnel is the world's longest train tunnel. (Photo by Arnd Wiegmann/Reuters)